Infection - Level 2 Flashcards
1
Q
Epidemiology of HIV?
A
- 110,000 people living with HIV in the UK.
- 5% MSM living in the UK has HIV.
- Black African people make up 36% of all people living with HIV in UK
2
Q
What is HIV and how does it progress?
A
o Retrovirus which infects and replicates in human lymphocytes (CD4 + T-Cells) and macrophages
Retrovirus encodes reverse transcriptase, allowing DNA copes to be produced from viral RNA, it is error prone
o Leads to progressive immune system dysfunction, opportunistic infection and malignancy=AIDS
o Subtypes include HIV1 (global epidemic) and HIV2 (low pathogenic, West Africa)
3
Q
Transmission of HIV?
A
Blood, sexual fluids and vertically (pregnancy, childbirth, breastfeeding)
4
Q
Risk Factors of HIV?
A
- Partner infected or from high risk area of HIV
- MSM
- Female sexual contacts of MSM
- Multiple partners
- History of STIs, Hep B, Hep C
- Migration from high prevalence countries (particularly sub-saharan Africa)
- Failure to use barrier contraception.
- IVDU
- Needle-stick injury
5
Q
Pathophysiology of HIV?
A
o HIV binds, via its GP120 envelope glycoprotein, to CD4 receptors on helper-T-cells, monocytes and macrophages
o CD4 cells migrate to lymphoid tissue where virus replicates, producing new virions
o Released and infect new CD4 cells
o As infection progresses, depletion or impaired function of CD4 cells leads to decreased immunity
6
Q
When is HIV most infective?
A
- Acute primary HIV infection is the time of highest infectivity.
- The risk of transmission per exposure via sex is relatively low (~0.1-3%).
7
Q
Symptoms and signs of primary HIV?
A
Primary HIV infection (seroconversion illness)
- Symptomatic in 80%, typically 2-4 weeks after infection
- Flu-like symptoms
o Fever
o Malaise
o Myalgia
o Lymphadenopathy
o Pharyngitis - Erythematous/Maculopapular rash
- Headache/Aseptic meningitis
- Unusual signs: oral thrush, recurrent shingles, leukopenia
8
Q
Symptoms and signs of asymptomatic HIV?
A
Asymptomatic infection (clinical latency)
- After seroconversion, virus levels low as replication continues
- CD4 and CD8 normal and may persist for many years
9
Q
Symptoms and signs of persistent generalised lymphadenopathy HIV?
A
- Swollen/Enlarged lymph nodes >1cm in 2 or more non-contiguous sites (not inguinal) persisting >3 months
- Due to follicular hyperplasia caused by HIV
- Exclude TB, infection and malignancy
10
Q
Symptoms of infections in HIV?
A
- Non-Specific symptoms
o Fever, night sweats, diarrhoea, weight loss - Minor opportunistic infection
o Oral thrush, oral hairy leukoplakia, HZV, recurrent shingles, tinea infection, seborrheic dermatitis
o Lymphopenia, thrombocytopenia
11
Q
WHO clinical stage 1 of HIV?
A
o Asymptomatic
o Persistent generalised lymphadenopathy
12
Q
WHO clinical stage 2 of HIV?
A
o Moderate unexplained weight loss (<10% presumed or measured body weight)
o Recurrent respiratory tract infections sinusitis, tonsillitis, otitis media and pharyngitis.
o Herpres zoster
o Recurrent oral ulceration
o Papular puritic eruptions
o Seborrhoeic dermatitis
o Fungal nail infections
13
Q
WHO clinical stage 3 of HIV?
A
o Unexplained severe weight loss (>10% of presumed or measured body weight), chronic diarrhoea for longer than 1-month, persistent fever (>37.6 degrees intermittent or constant, longer than 1 month).
o Persistent oral candidiasis
o Oral hairy leukoplakia
o Pulmonary tuberculosis
o Severe bacterial infections (pneumonia, empyema, pyomyositis, bone/joint infections, meningitis or bacteraemia).
o Acute necrotising ulcerative stomatitis, gingivitis or periodontitis.
o Unexplained anaemia (<8g/dL), neutropenia (<0.5 x 109/L) or chronic thrombocytopenia (<50 x 109/L)
14
Q
WHO clinical stage 4 of HIV?
A
o HIV wasting syndrome (weight loss with diarrhoea or weakness and fever)
o Pneumocystis jirovecii pneumonia, recurrent severe bacterial pneumonia
o Chronic HSV (orolabial, genital or anorectal for more than one month or visceral at any site).
o Oesophageal candidiasis (or candidiasis of trachea, bronchi or lungs).
o Extrapulmonary tuberculosis
o Kaposi’s sarcoma
o CMV (retinitis or infection of other organs)
o CNS toxoplasmosis
o HIV encephalopathy
o Extrapulmonary cryptococcosis including meningitis
o Disseminated non-tuberculous mycobacterial infection
o Progressive multifocal leukoencephalopathy
o Chronic cryptosporidiosis (with diarrhoea)
o Chronic isoporiasis
o Disseminated myocisis (coccidomycosis or histoplasmosis)
o Recurrent non-typhoidal Salmonella bacteraemia.
o Lymphoma (cerebral or B-cell non-Hodgkin) or other solid HIV associated tumours.
o Invasive cervical carcinoma
o Atypical disseminated leishmaniasis
o Symptomatic HIV-associated nephropathy or symptomatic HIV associated cardiomyopathy.
15
Q
When should HIV testing be offered?
A
o All at risk patients Anyone with STI MSM Buying/Selling sex From countries of high HIV prevalence IVDU Any sexual partner of the above o Blood or organ donation o Opt out screening – attendees of sexual health clinics, antenatal screening
16
Q
Benefits of HIV testing?
A
Negative - Reassurance, motivation to maintain behaviours
Positive – Effective treatment to reduce morbidity, better prognosis, reduce risk of inadvertent transmission
17
Q
What 2 tests are offered to diagnose HIV? Describe process of diagnosing HIV?
A
o ELISA + Western Blotting for HIV antibody and p24 antigen
Assays for HIV1, HIV2 and HIVp24 antigen
Send 10mls of clotted blood to virology, marked HIV test
Window period up to 12 weeks
If positive, diagnosis confirmed by confirmatory assay
If negative, reassuring but repeat at 3 months
If at risk – 3-6 monthly testing
o Point-of-care Tests
Finger-prick or mouth samples used in some GUM clinics, results within 1 hour (can be used in acute setting)
If positive, lab test done
18
Q
Other tests used in HIV monitoring? and their uses?
A
o CD4 Count
Used to monitor immune system function and disease progression (<200 cells/microlitre is AIDS)
o Viral Load
Quantification of HIV RNA
Used to monitor response to ART
Not diagnostic so care of use in symptomatic window period – need confirmation of seroconversion
o Nucleic Acid Testing/Viral PCR
Test for viral RNA, used in vertical transmission in neonates
o Routine Bloods
FBC, U&E, LFT, lipid/bone profile, glucose
19
Q
Prevention and management of needle stick injury in patient with HIV?
A
- Risk of HIV transmission from single needle-stick exposure from person with HIV not on ART is 1 in 300
- Prevent
o Use safer sharps (mechanism to minimise injury)
o Do not recap medical sharps
o When using sharps, ensure disposal container near - Manage
o Encourage wound to bleed, ideally under running water (do not suck)
o Wash with soap and running water, do not scrub
o Contact OH/infection control (or A&E outside working hours) regarding testing and post-exposure prophylaxis
20
Q
Monitoring in HIV infection?
A
- Clinical assessment
- CD4 count
- Plasma HIV RNA levels
- 6-monthly review at GP
- Annual full sexual health screen
21
Q
Management of new diagnosis of HIV - referral?
A
- Refer urgently (within 48 hours, no later than 2 weeks) to GUM or HIV specialist
22
Q
Management of new diagnosis of HIV - general measures?
A
Sex safe promotion (barrier contraception, dangers of multiple partners)
Needle exchange schemes
Vaccine for HepB, pneumococcal and Hib, influenza and swine flu
Partner notification
Speak to GUM if not willing
Estimate date when infection occurred, all contacts within 90 days prior to infection
If estimate cannot be made, all prior partners should be informed
23
Q
Management of new diagnosis of HIV - follow up?
A
- Follow Up in 1-2 days
24
Q
Contact tracing in new diagnosis of HIV?
A
Speak to GUM if not willing
Estimate date when infection occurred, all contacts within 90 days prior to infection
If estimate cannot be made, all prior partners should be informed
25
What is ART management?
- Antiretroviral therapy (ART) used in everyone with HIV
- Aims to reduce HIV viral load to undetectable level leading to immunological recovery, reduced clinical progression and reduced mortality
26
Mechanism of HAART - NRTI/NNRTI?
o Nuclotide/Non-nucleoside reverse transcriptase inhibitors (NRTI/NNRTI)
Inhibit reverse transcriptase and conversion of viral RNA into DNA
• NRTI – Zidovudine, abacavir, didanosine, lamivudine
• NNRTI – Efavirenz, etravirine, nevirapine, rilpivirine
27
Mechanism of HAART - Protease inhibitors?
o Protease Inhibitors
Inhibit HIV enzymes required to produce mature infectious particles by cleaving structural proteins and enzymes
Atazanavir, darunavir, fosamprenavir, indinavir, lopinavir, ritonavir
28
Mechanism of HAART - CCR5 antagonist?
o CCR5 Antagonist
Inhibit entry of virus into cell by blocking CCR5 co-receptor
Maraviroc
29
Mechanism of HAART - Integrase inhibitor?
o Integrase inhibitor
Dolutegravir, elvitegravir, raltegravir
Used in HIV infection resistant to 1st line
30
Investigations to perform when starting HAART?
o Counselling – health promotion, not a cure and lifelong therapy, side effects of treatment
o Screen for infections and malignancy (TB and HepB&C)
o Baseline tests – CD4, viral load, FBC, LFT, U&E, pregnancy test, viral genotype
31
1st line drug regimen in HAART in HIV?
o 2 NRTIs + one of:
Ritonavir-boosted protease inhibitor
NNRTI
Integrase inhibitor
32
1st line NRTIs used in HAART for HIV?
Tenofovir + Emtricitabine (Truvada), abacavir + lamivudine (Kivexa)
SE: GI disturbance, anorexia, pancreatitis, lactic acidosis, low bone density
33
1st line Protease inhibitors used in HAART for HIV?
Atazanavir, darunavir, fosamprenavir, indinavir, lopinavir, ritonavir
SE: hyperglycaemia, insulin resistance, dyslipidaemia, jaundice, hepatitis
34
1st line NNRTIs used in HAART for HIV?
Rilpivirine (give with food), efavirenz (CNS toxicity, care in depression, adverse lipids, rash)
35
1st line Integrase inhibitors used in HAART for HIV?
Dolutegravir, elvitegravir, raltegravir
| SE: rash, GI disturbance, insomnia
36
1st line regimen choice in HAART for HIV?
o Tenofovir + emtricitabine (Truvada) + efavirenz/atazanavir/darunavir
o Abacavir + lamivudine (Kivexa) + lopinavir with ritonavir/fosamprenavir/nevirapine/rilprivirine
37
Aims of HAART treatment in HIV?
o Reduce viral load to <50copies/ml within 4-6 months
38
Primary prevention of infections used in HIV?
- PCP – co-trimoxazole if CD4 <200
39
What is Post-exposure prophylaxis in HIV?
- Short-term use of ART recommended ASAP after potential sexual or occupational exposure (up to 72h, ideally <24h)
- Need to assess level of risk with OH or specialist
40
1st line PEP in HIV?
```
o Truvada (tenofovir +emtricitabine) and raltegravir for 28 days
o Test for HIV 8-12 weeks after exposure
```
41
What is Pre-exposure prophylaxis in HIV?
- Used in HIV-negative patients with high risk of acquiring HIV including serodifferent relationships without suppression of viral load, condomless anal in MSM
- Taken before, during and after – daily or around sexual activities
42
Drug used in PrEP in HIV?
- Truvada used (Emtricitabine + Tenofovir)
43
Is HIV tested in pregnancy?
• HIV blood test as part of the routine antenatal screening.
44
Contraception counselling advice in HIV?
* Where the mother is positive and the partner negative, self-insemination with the partner’s sperm is recommended.
* If the male is positive and the female is negative, sperm washing is recommended (alternatively, donor insemination is an option).
* IVF should take account of the parents’ viral load, CD4 counts and any AIDS defining illness.
* Consideration should be given to current therapy (HAART) as there is the possibility of teratogenicity with some drug combinations of taking folate antagonists for PCP prophylaxis.
45
Testing in patient with HIV and pregnant?
o HIV test at booking
Testing of other children is recommended.
o Check for Hep B, Hep C, VZV, measles and toxoplasmosis antibodies
o Offer Hep B, pneumococcal and influenza vaccine
o Screening for STI’s should be performed at booking and 28 weeks
o Treat asymptomatic infections
o Viral load and CD4 count should be repeated every 3 months and specifically at 36 weeks to inform neonatal therapy
46
HAART management during pregnancy for patient with HIV?
o Continue in pregnancy if needed for mothers’ health
o If not needed, start HAART by 24 weeks until delivery
cART
If viral load <10000 and elective CS – ZDV monotherapy between 20-28 weeks, then IV ZDV 4 hours before CS until cord clamped
o Warm about risk of GDM and premature labour
47
How to prevention vertical transmission of HIV in pregnancy?
- Antenatal HAART (highly active antiretroviral therapy)
- Delivery by CS
- Avoidance of breast feeding
48
Delivery in patient with HIV - premature labour?
o If membranes rupture >34 weeks, expedite
o If membranes rupture <34 weeks, give steroids, erythromycin, HAART regimen and seek HIV specialist review
o If no membrane rupture, manage as if HIV negative
49
Delivery in patient with HIV - C-section?
- 38 weeks
- If viral load >50 (>400 on HAART), or co-infected with Hep C and not on HAART
- If viral load <50 – plan for 39+ weeks
- Performed within 4 hours of SROM.
- HAART needed if not on medication
- Early clamping of the cord is recommended
50
Delivery in patient with HIV - vaginal delivery?
- Viral loads <50 (<400 if on HAART)
- Continue HAART in labour
- Avoid foetal blood sampling/scalp electrodes/amniotomy unless delivery imminent
- Oxytocin augmentation can be used
- Low cavity forceps preferred (avoid mid -cavity or rotational)
51
Delivery in patient with HIV -HAART?
cART for advanced disease
- ART initiated by 24th week and discontinued at delivery
- If viral load <10000 and elective CS – ZDV monotherapy between 20-28 weeks, then IV ZDV 4 hours before CS until cord clamped
52
Neonatal treatment to baby born to HIV positive mother?
cART for advanced disease
- ART initiated by 24th week and discontinued at delivery
- If viral load <10000 and elective CS – ZDV monotherapy between 20-28 weeks, then IV ZDV 4 hours before CS until cord clamped
53
When to test neonate after birth to HIV positive mother?
o HIV DNA PCR (or HIV RNA testing):
o Day 1, 6 weeks and 12 weeks
o Confirmatory HIV antibody testing at 18 months
54
Definition of AIDS?
• The development of opportunistic infections or malignancy (including cervical carcinoma) or a CD4 count <200 cells/mm3 are diagnostic of AIDS.
55
Common AIDs defining diseases?
Pneumocystitis pneumonia
Oesophageal candida
Non-Hodgkin’s lymphoma
Tuberculosis (pulmonary and extra pulmonary)
56
Side effects of HAART medications?
- Common side effects include: collection of fat on the back (buffalo hump) and abdomen, diarrhoea, malaise, headache, nausea, weakness, high glucose, high cholesterol
57
Definition of influenza?
- Acute respiratory illness caused by RNA viruses of Orthomyxoviridae (influenza viruses)
58
Types of influenza?
o Influenza A – more frequent and more virulent, responsible for local outbreaks, large epidemics and pandemics
o Influenza B – co-circulates with influenza A during yearly outbreaks, less severe
o Influenza C – mild or asymptomatic infection similar to common cold
- Seasonal outbreaks divided by H and N antigens on virus
59
What is uncomplicated influenza?
o Acute infection usually self-limiting in general population
60
What is complicated influenza?
o More severe, usually Influenza A
| o Symptoms that require hospital admission, involve LRT, exacerbated pre-existing medical condition
61
Epidemiology of influenza?
- Occurs during winter months, typically between December and March
62
Symptoms of uncomplicated influenza?
```
o Coryza, nasal discharge
o Cough
o Fever
o GI upset
o Headache, malaise, myalgia, arthralgia
o Photophobia, conjunctivitis
o Sore throat
```
63
Symptoms of complicated influenza
o Signs and symptoms that require hospital admission
o LRTI
o CNS involvement
o Exacerbation of underlying medical condition
64
Management of influenza - general advice?
o Drink adequate fluids
o PRN paracetamol and ibuprofen
o Bed rest
o Stay off work until feel able to attend
o Symptoms usually resolve within 1 week, may be up to 2 weeks
65
Management of influenza - safety net?
o Warn about complicated symptoms
Signs and symptoms that require hospital admission
LRTI
CNS involvement
Exacerbation of underlying medical condition
o If develop SOB, CP or haemoptysis or no improvement within 1 week – follow up
66
Management of influenza - admission?
Complication of influenza – pneumonia
Co-existing medical condition that puts them at high risk
Under 2 years old and in high risk group
67
Management of influenza - antiviral therapy - when to give?
Antiviral (oral oseltamivir or inhaled zanamivir) if:
National survery indicates influenza is circulating
Person is ‘at risk’
• >65 years, <6 months, pregnant women and 2 weeks post-partum
• Asplenia
• COPD, bronchiectasis, CF, Asthma (continuous or repeated use of corticosteroids)
• CHD, CHF, IHD,
• CKD,
• Cirrhosis, biliary atresia, hepatitis,
• TIA, stroke,
• T1DM, T2DM, Immunosuppression,
• BMI >40
Person can start treatment within 48 hours of onset of symptoms (36 in zanamivir)
68
Management of influenza - post exposure prophylaxis?
o DO NOT consider in at-risk groups if vaccinated >14 days before exposure
o Only prescribe if:
National surveillance indicates influenza circulating
Person exposed (in same household)
At risk group and not adequately protected by vaccine
Able to start treatment within 48 hours of contact (oseltamivir) or 36 (zanamivir)
o Arrange flu jab
69
Management of influenza - prevention?
Vaccination (quadrivalent – 2 types of A & B)
o How to give:
Adults – IM injection in deltoid
Children 2-10 - Intranasal spray in each nostril
70
Management of influenza - when to give vaccine?
All people aged >65 (adjusted trivalent or quadrivalent)
All people aged 6 months to 65 years in clinical risk group:
• Respiratory – COPD, bronchiectasis, CF, IPF, BPD, asthma (continuous or repeated corticosteroids or previous hospital admission)
• Cardiac – congenital HD, hypertension with cardiac complications, CHF, IHD
• CKD
• Liver – Hepatitis, cirrhosis, biliary atresia
• Neurological – TIA, stroke, cerebral palsy, Parkinson’s, MS, MND, polio
• T1DM, T2DM
• Immunosuppressed – chemo, bone marrow transplant, myeloma, HIV/AIDs, DMARDs, systemic corticosteroids (>1 month)
• Asplenia
• Pregnant women
• BMI >40
Children aged 2-10 (LAIV)
People in long-stay residential and nursing homes
Close contacts of immunocompromised people
71
Management of influenza - contraindications to influenza vaccine?
Allergy (if true egg allergy – may need admission for it)
| Acutely unwell (febrile, systemic infection)
72
Management of influenza - adverse effects of influenza vaccine?
Pain, swelling, redness at site
Low-grade fever, malaise, fatigue
Headache, myalgia
73
Complications of influenza?
o Respiratory - Acute bronchitis, exacerbation of asthma or COPD, otitis media, pneumonia, sinusitis
o Cardiac - Myocarditis, pericarditis
o Febrile convulsions
o Myalgia, myositis
o Neurological – Reyes syndrome, encephalomyelitis, GBS, aseptic meningitis
o Toxic shock syndrome
74
Definition of measles? Transmission? Incubation?
- RNA paramyoxyviridae virus
- Highly infectious
- Transmitted by droplets / direct contact
- Incubation period: 7-14 days
- Infectious 4d before symptoms and 4d after onset of rash
75
Epidemiology of measles?
- Peak age= <1 year (before immunisation) or older children that are not immunised
- Occurs typically in preschool children - peak in winter/spring
- Commonest in developing countries
- Rare due to MMR vaccine
76
Risk factors of measles?
- Not immunised, immunocompromised, contact
77
Symptoms of measles?
- Prodrome (2-4 days) of:
o Fever 39oC
o Conjunctivitis, coryza, cough, lymphadenopathy
o Koplik’s spots (grain like spots opposite lower molars and buccal mucosa)
- Rash appears 3-4 days later usually on face & behind ear and spreads to whole body
o Initially erythematous and maculopapular but then blotchy and conflueunt, may desquamate in 2’ wk.
78
Diagnosis of measles?
- Clinical diagnosis confirmed by serology &/ or viral culture (oral fluid sample)
- Blood Film
o Leucopenia, lymphopenia
79
Management of measles - general advice?
- Notifiable disease to Health Board
o Testing kit – oral fluid sample for IgG/IgM and/or RNA testing
o Seek advice from HPT about immunosuppressed, pregnant and infants <1
- Supportive – Antipyretics, ibuprofen and fluids
- Stay off school/work for 4 days after development of rash
- Avoid contact with people not vaccinated, infants, pregnant women or immunocompromised
80
Management of measles - if susceptible and >1, pregnant or immunosuppressed?
o Give immediate MMR vaccine
81
Management of measles - if immunocompromised?
o Ribavirin
82
Prognosis of measles?
o Most people with measles make full recovery after a week
83
Complications of measles?
```
- Common
o Otitis Media
o Pneumonia
o Tracheobronchitis
o Diarrhoea
```
- Rare
o Convulsions
o Encephalitis
o Subacute Sclerosing Panencephalitis
84
Definition of mumps? Incubation time? Infective?
- Acute infection caused by RNA paramyoxavirus
- Droplet/Saliva spread and replicates in upper respiratory mucosa
- Incubation time - 14-21 days
- Infective – 7 days before and 9 days after parotid swelling starts
85
Epidemiology of mumps?
- Introduction of MMR has reduced rates of mumps
- 90% in people >15
- Rare in children <1 due to passive immunity
86
Risk factors of mumps?
- Likely in unimmunised, recent contact or outbreak of mumps in local area
87
Symptoms of mumps?
o Prodromal malaise
o High temperature
o Painful parotid swelling (typically one side first, then bilateral in 70%)
Ear lobe deflected upwards and outwards
Angle of mandible obscured
Pain when chewing, speaking
88
Investigations of mumps?
- Clinical Diagnosis
| - Confirmed by saliva sample to detect presence of IgM mumps antibody
89
Management of mumps - notify public health?
o Arrange testing kit through saliva swab
90
Management of mumps -general advice?
o Self-limiting – resolves over 1-2 weeks
o Bed Rest
o Drink adequate fluids
o PRN paracetamol and ibuprofen
o Warm/Cold packs to parotid gland
o OFF SCHOOL/WORK FOR 5 DAYS AFTER INITIAL DEVELOPMENT OF PAROTIDITIS
o 1-week follow up to check symptoms resolving and immunised
91
Management of mumps -contacts?
o Offer MMR if not fully immunised
92
Management of mumps -pregnant women?
o Manage in same way, MMR is CI in pregnancy
93
Management of mumps -if epididymo-orchitis diagnosed?
o Symptomatic relief
o Symptoms should resolve in 2 weeks
o If concerned about fertility issues, offer semen analysis 3 months after mumps resolved
If abnormal then refer to fertility specialist
94
Management of mumps -admission?
o Mumps encephalitis or meningitis
95
Prognosis of mumps?
o Self-limiting disease that resolves within 1-2 weeks and most recover without any long-term complications
96
Complications of mumps?
```
o Usually none
o Parotiditis
o Epididymo-orchitis (+/- infertility)
o Oophoritis
o Arthritis
o Meningitis
o Pancreatitis
o Myocarditis
o Deafness
```
97
Definition of rubella? Transmission? Incubation period? Infectivity?
- Infectious RNA togaviridae viral illness, Rubella virus spread via air-droplets
- Known as German measles or three-day measles
- Transmitted by droplet spread or via placenta to foetus
- Incubation period = 14-21 days
- Infectious: most infectious when rash erupting but 7 days before to 7 days after rash appears
- Prevention of Spread – MMR vaccine at 12-15 months, booster at 4-6 years
98
Epidemiology of rubella?
- 1/25,000
| - Peak age: >15 years
99
Risk Factors of rubella?
- Malnutrition, not immunised, immunocompromised, contact with Rubella
100
Symptoms if caught during pregnancy of rubella? ?
o Teratogen during pregnancy
Infection before 8 weeks leads to cataracts, congenital heart defects and deafness
• Congenital Rubella Syndrome
101
Symptoms of rubella?
- Clinical Features 2-3 weeks after exposure and include:
o Rash – Pink or light red maculopapular rash starts on face which spreads to chest, upper arms, abdomen and thighs
o Lymphadenopathy (suboccipital, postauricular and cervical lymph nodes)
o Arthralgia and arthritis
o Malaise
o Low-grade Fever
o Headache
o Coryza
o Non-purulent conjunctivitis
102
Investigations of rubella?
- Clinical diagnosis
| - Confirmed by serology &/ or viral culture
103
Management of rubella - notifying HPT?
o Notifiable disease – inform HPT
o Discuss need for testing
Immediate oral fluid sample for serology and PCR may be requested – if positive then further testing needed
May need to test for other infections
104
Management of rubella - general advice?
Normally self-limiting – resolve within 1 week
Supportive – Antipyretics, keep hydrated
Avoid school for 5 days after development of rash
Avoid contact with pregnant women
105
Management of rubella - pregnant women - if confirmed and <20 weeks?
Refer urgently to obstetrics for risk-assessment (lower gestation, the higher risk of CRS)
106
Management of rubella - pregnant women - if confirmed and >20 weeks?
Reassure that no reported cases of CRS after this age
| Give rubella vaccine post-partum only
107
Complications of rubella in healthy people?
o Arthritis and arthralgia
| o Encephalitis rare
108
Complications of rubella in pregnant women?
Miscarriage, stillbirth and Congenital Rubella Syndrome
o Cataracts, hearing impairment, PDA and pulmonary artery stenosis, microencephaly, mental retardation, IUGR, autism, DM and thyroid dysfunction
109
Definition of Chicken Pox?
- Highly infectious disease caused by herpes virus transmitted by air droplets
- VZV infection between 1-6yrs commonly —winter/spring
110
Transmission of Chicken Pox?
- Transmission is by personal contact or droplet spread, with an incubation period (the time from becoming infected until symptoms appear) of 1-3 weeks
111
Infectivity of Chicken Pox?
- Chickenpox is infectious from 1-2 days before the rash appears until the vesicles are dry or have crusted over, usually 5 days after the onset of the rash
112
What is Herpes Zoster Virus?
- Herpes Zoster (shingles)
o a reactivation of the latent infection may occur -> vesicular lesions in the distribution of the sensory nerve. Increased risk in immunosuppressed
113
Epidemiology of Chicken Pox?
- Incidence is highest before 10 years of age
- >90% of people older than 15 years of age UK are immune
- Peak incidence from March-May
114
Cause of Chicken Pox?
- Caused by varicella-zoster virus (VZV)
115
Symptoms of Chicken Pox?
Prodrome:
- Infection begins 2 days before vesicles appear
- Infection ends when last vesicle crusts over
Rash:
- Head and trunk rest of body.
- Red macules papulevesiclepustulecrusting
- Crusting within 5 days and fall off after 1-2 weeks
Other features: headache, anorexia, URTI (sore throat, coryza, cough), fever and itching
116
Investigations of Chicken Pox?
Ex: Characteristic rash, its distribution and progression
| Laboratory tests, rarely required
117
Management of Chicken Pox - general advice?
o Usually self-limiting
o Encourage fluid intake
o Wear smooth, cotton fabrics
o Keep nails short to minimise damage from scratching
o Avoid contact with immunocompromised, pregnant women and infants <4 weeks until 5 days after rash
o School/nursery exclusion until all lesions crusted over
118
Management of Chicken Pox - symptomatic advice?
o Paracetamol
o Calamine lotion
o Chlorphenamine
119
Management of Chicken Pox - if >14, presenting within 24 hours of rash and severe or risk of complications (smoker)?
o Consider Aciclovir PO 800mg 5x/day
120
Management of Chicken Pox -admission?
- Admit if severe complications (pneumonia, encephalitis, dehydration)
121
Management of Chicken Pox - pregnant women - admission?
- Admit to hospital if pregnant woman has:
o Respiratory symptoms, neurological symptoms, haemorrhagic rash or bleeding, dense rash with mucosal lesions, immunosuppressed
- All other women:
o Seek specialist advice from obstetrician
122
Management of Chicken Pox - pregnant women - drug management?
o Oral aciclovir
o Symptomatic Treatment
Paracetamol
Calamine lotion
123
Management of Chicken Pox - pregnant women - general advice?
Usually self-limiting
Encourage fluid intake
Wear smooth, cotton fabrics
Keep nails short to minimise damage from scratching
Avoid contact with immunocompromised, pregnant women and infants <4 weeks until 5 days after rash
School/nursery exclusion until all lesions crusted over
124
Manageemnt of exposure to chicken pox?
- Significant exposure if mother, continuous home contact, contact in same room for 15 minutes, face to face contact
- If pregnant woman and never had chicken pox – Test for IgG VZV and if negative seek specialist advice
- If immunocompromised or neonate – immediate specialist advice
125
Complications of Chicken Pox in pregnancy?
- Varicella in pregnancy can result in severe chickenpox
- Infection during 1st 28 weeks of pregnancy can lead to intrauterine infection and foetal varicella syndrome
o Skin scarring in dermatomal distribution, microphthalmia, chorioretinitis, cataracts, hypoplastic limbs, microcephaly
126
Complications of Chicken Pox?
- Secondary bacterial infection
o Due to staphylococcal/streptococcal leading to toxic shock syndrome or necrotising fasciitis
- Encephalitis
o Cerebellitis, meningitis
- Purpura fulminans
o Vasculitis in the skin due to cross-reactivity of antiviral antibodies
- Immunocompromised can disseminate causing pneumonitis/DIC – fatal 20%
127
Definition of whooping cough?
- Pertussis - a highly infectious form of bronchitis
128
Epidemiology of whooping cough?
- Usually epidemics every 3-4 years
| - Incidence is increasing
129
Risk factors of whooping cough?
o Young Infants
o Unvaccinated children
o Immunocompromised
130
Cause of whooping cough?
- Caused by Bordetella pertussis
| - Spread with close contact of air-born droplets
131
Symptoms of whooping cough - catarrhal phase?
```
Nasal discharge
Conunctivitis
Malaise
Sore throat
Low-grade fevfer
Dry, unproductive cough
```
132
Symptoms of whooping cough - paroxysmal phase?
o Paroxysmal Phase (1-6 weeks)
Coughing fits (paroxysms)
Short expiratory burst followed by inspiratory gasp, causing whoop sound
More common at night and triggered by stimulus (cold, noise)
Can cause cyanosis, post-tussive vomiting
133
Symptoms of whooping cough - convalescent phase?
o Convalescent Phase (3 months)
| Gradual improvement in cough
134
Signs of whooping cough?
o During paroxysm child goes red or blue in face
o Whoop may be absent in infants
o Apnoeas common in infants
o Epistaxis and sub-conjunctival haemorrhages can occur after vigorous coughing
o Exhausted by coughing
135
Diagnosis of whooping cough?
```
- Clinical Diagnosis
o If acute cough >14 days without cause and has:
Paroxysmal cough
Inspiratory whoop
Post-tussive vomiting
Undiagnosed apnoeic attack in infants
```
136
Management of whooping cough - notification and testing?
- Notify local Public Health England centre within 3 days
o If cough <2 weeks – culture nasopharyngeal aspirate or swabs
o If <3 weeks duration – PCR testing of nasopharyngeal/throat swabs
o If cough >2 weeks – anti-pertussis toxin IgG detection in serology (over 16) or oral fluid (children 5-16 years)
137
Management of whooping cough - when is diagnosis confirmed?
Bordetella pertussis on aspirate/swab, PCR detection of pertussis or anti-pertussis toxin IgG in serum/oral fluid in abscnece of vaccine within the last year
138
Management of whooping cough - admit?
o <6 months and acutely unwell
o Apnoeas/Severe paroxysms/Cyanosis
o Complication (seizures, pneumonia)
139
Management of whooping cough - general measures?
o Rest
o Adequate fluid intake
o Paracetamol and ibuprofen
o Avoid school/work/nursery until 48 hours of antibiotics or 21 days after onset of cough
140
Management of whooping cough - antibiotic therapy?
```
o If onset of cough within 21 days:
Clarithromycin if <1 month of age
Clarithromycin or azithromycin if >1 month old
Erythromycin in pregnant women
• Alternative – co-trimoxazole
```
141
Management of whooping cough - antibiotic prophylaxis - who?
When case within 21 days and close contacts in one of these groups:
Group 1 – unimmunised infant born <32w <2m, unimmunised infant born >32w and <2m if mother did not have pertussis vaccine, infant >2m who are unimmunised
Group 2 – Pregnant woman >32 weeks, healthcare worker with infants or pregnant women, people sharing household with infant too young to vaccinated
142
Management of whooping cough - antibiotic prophylaxis - what?
Clarithromycin if <1 month of age
Clarithromycin or azithromycin if >1 month old
Erythromycin in pregnant women
• Alternative – co-trimoxazole
143
Definition of gastro-enteritis?
- Decreased stool consistency from water, fat or inflammatory discharge
144
Classification of gastro-enteritis?
- Acute <2 weeks
| - Persistent >2 weeks
145
Definition of dysentery?
o Loose stools with blood and mucus
o Organisms that cause bloody diarrhoea include campylobacter, entamoeba histolytica, E.coli, salmonella serotypes and Shigella
146
Definition of Traveller's Diarrhoea?
o Diarrhoea starting during or shortly after foreign travel
| o Organism most commonly E.coli, Salmonella, Viruses, Cryptosporidium, Giardia
147
Common causes of diarrhoea?
```
- Common Causes
o Gastroenteritis
o Parasites/protozoa
o IBS
o Colorectal cancer
o IBD
- Drugs
o Antibiotics, PPI, NSAIDs, laxative, alcohol, cytotoxics
- Rarer Causes
o Chronic pancreatitis, laxative abuse, lactose intolerance, overflow diarrhoea, ileal resection, thyrotoxicosis, Ischaemic colitis
```
148
Cause of gastro-enteritis?
o Often contaminated food, usually meat, egg or milk products which been prepared inadequately
149
Types of diarrhoea and their cause?
o Bloody Diarrhoea
Campylobacter, Shigella/Salmonella, E.coli, amoebiasis
IBD, colorectal cancer, colonic polyps, colitis
o Mucous
IBS, colorectal cancer, polyps
o Frank Pus
IBD, diverticulitis, abscess or fistula
o Explosive
Cholera, giardia, rotavirus
150
Important history questions in gastro-enteritis?
o Important questions – duration, frequency, food and water intake, cooking method, time until onset, other diners affected, any swimming or canoeing
151
Assessment of dehydration in gastro-enteritis?
o Mild – anorexia, nausea, light headedness, postural hypotension
o Moderate – tiredness, dizziness, nausea, headache, muscle cramps, dry tongue, sunken eyes, reduced skin turgor, tachycardia, oliguria
o Severe – Profound apathy, weakness, confusion, shock, tachycardia, peripheral vasoconstriction, low BP, anuria/oliguria
152
Investigations in gastro-enteritis?
o FBC, ESR/CRP, U&E, TSH, coeliac serology
153
When to do stool culture in gastro-enteritis?
o Only used if patient has been abroad, severely ill, prolonged symptoms or works as food-handler
154
Food associated with S.aureus?
Meat
155
Food associated with Bacillus Cereus?
Rice
156
Food associated with Salmonella?
Meat, eggs, poultry
157
Food associated with C.botulinum?
Processed food
158
Food associated with V.cholerae?
Water
159
Associated with C.diff?
Abx associated
160
Food associated with Campylobacter?
Milk, poultry, water
161
Food associated with Listeria?
Cheese, pate
162
Associated with E.coli 0157?
HUS
163
Associated with norovirus?
Faecal oral spread, very contagious
164
Food associated with Shigella?
Any Food
165
Management of gastroenteritis - prevention?
o Hygiene (hand, water sources, no ice cubes, salads)
o Eat only freshly prepared hot food
o Food handlers – no work until stool samples negative
166
Management of gastroenteritis - symptomatic treatment?
Usually self-limiting
Maintain oral intake
ORT (Dioralyte) – contains glucose, Na, K, Cl
Loperamide if mild-to-moderate traveller’s diarrhoea
• Avoid in bloody or inflammatory dysentery and significant abdominal pain
167
Management of gastroenteritis - when to admit?
seriously ill, dehydrated >5%, high fever, infants
168
Management of gastroenteritis - Fluid therapy if shocked?
IV saline bolus 500ml (in children 20ml/kg)
169
Management of gastroenteritis - Fluid therapy if not shocked?
Encourage oral intake (in children – ORS 50ml/kg, continue breastfeeding, avoid fruit jucie and carbonated drinks)
170
Management of gastroenteritis - IV Fluid therapy if adult?
IV fluids 0.9% saline + 20mmol/L K/L IVI
171
Management of gastroenteritis - IV Fluid therapy if child?
Deficit 0.9% NaCl (100ml/kg if shocked, 50ml/kg if not),
Maintenance (100ml/kg/day for 1st 10kg, 50ml/kg/day for 2nd 10kg, 20ml/kg/day for subsequent kg)
172
Management of gastroenteritis - antibiotic therapy?
• Ciprofloxacin
| o If systemically unwell, elderly, immunosuppressed, Salmonella, shigella or campylobacter
173
Definition of malaria?
- Infection of RBCs by plasmodium parasites including:
| o P.falciparum, P.vivax, P.ovale, P.malariae
174
Transmission of malaria?
- Transmission through bite of infected female Anopheles mosquito
o Sporozoite inoculated into humans in saliva of mosquito
o Travels in blood stream to the liver, enter liver cells and mature into schizonts which rupture and release thousands of merozoites
o Each merozoite infects a RBC where they divide and reupture
- Found in tropical and subtropical area
175
Causes of malaria and their distribution?
.falciparum – African continent, most common, incubation 7-10 days and symptoms recur 36-48 hourly
o P.vivax – Asia, Latin America, Africa, incubation period 10-17d and can remain dormant for months
o P.ovale – Africa, western Pacific, dormant for months
o P.malariae – South America, Asia, Africa, chronic infection, incubation 18-40d, recurs 72 hourly
o P.knowlesi – from monkeys in Asia, can be fatal
176
Features of malaria?
o Usually present within 6 months of exposure
177
Symptoms of malaria?
```
o Fever (often >39o, and spikes), sweat, chills
Shivering <1h
Hot, fever 2-6h
Sweats as temperature falls
o Headache
o Malaise, lethargy, fatigue
o Anorexia, nausea, vomiting, diarrhoea
o Myalgia, arthralgia
o Sore throat, cough
```
178
Symptoms of severe malaria?
```
o Cerebral – GCS <11 or seizures
o Renal impairment
o Acidosis
o Hypoglycaemia
o RDS
o Anaemia
o Bleeding
o Shock, sepsis
```
179
Bloods taken in malaria?
o Thick and thin blood film microscopy
| o Antigen Detection Test
180
Management of malaria - prevention?
Avoid travel if high risk (pregnant, child, age >70, immunosuppression)
Avoid risk factors:
Outside between dusk and dawn, unscreened accommodation
PPE: insect repellent (20% DEET or icardin), protective clothing, insecticide impregnated bed nets
Chemoprophylaxis
Start 1 week before travel, for 4 weeks
Chloroquine, mefloquine, proguanil hydrochloride
Standby emergency medication if remote areas without medical facilities for 24 hours
Upon return - if develop any illness within 1st 3 months to see doctor immediately
181
Management of malaria -admission of acute infection?
o Admit any person with suspected severe or complicated malaria, falciparum malaria, pregnant, child or >65
182
Management of malaria - discussion in anyone with suspected malaria?
o Urgently discuss all other patients with ID specialist with view to admission for rapid blood testing
o Notify PHE
183
Management of malaria - general advice?
Warn that if family members get symptoms to see doctor
Notified to PHE
Relapses can occur
Excluded from blood donation
184
Management of malaria -immediate referral to ID or MAU for blood testing?
* Severe, complicated or falciparum malaria
* Pregnant
* Child
* >65 years
185
Management of malaria - testing in ID or MAU?
• Thick and thin blood films
o If negative, further blood test 12-24 hours later and again after 24 hours
o Calculate percentage of RBC parasitized
* Antigen Detection Test if blood films not available
* FBC (anaemia, thrombocytopenia), Clotting (DIC). Glucose (low), U&E (renal failure)
* ABG (lactic acidosis)
* Urinalysis (protein, blood, casts)
* Blood Culture – rule out sepsis
186
Management of malaria - drug management - if species not known?
o Artemether with lumefantrine (ACT)
o Quinine
o Atovaquone with proguanil
187
Management of malaria - drug management -if uncomplicated falciparum malaria?
Artemether with lumefantrine (ACT)
Atovaquone with proguanil
Quinine (IV if severe)
• Oral given for 5-7 days, with or followed by oral doxycycline for 7 days
188
Management of malaria - drug management - if complicated falciparum malaria?
IV Artesunate or Quinine
189
Management of malaria - drug management - if non-falciparum malaria (P.v, P.o, P.m, P.k)?
o Chloroquine
o If resistant then use artemether-lumefantrine
o If P.v or P.o – use chloroquine + primaquine after for 14 days
190
Management of malaria - drug management - cerebral malaria?
Manage fluids
Haemofiltration
Ventilation
Exchange transfusion if severe
191
Prognosis of malaria?
o If identified, appropriate treatment is given and no organ dysfunction – most people make rapid recovery
o If delayed – severe or fatal malaria can develop
o Death more likely in >65
o In pregnancy – pulmonary oedema and hypoglycaemias
192
Complications of malaria?
```
o Cerebral malaria
o ARDS
o Coagulopathy
o Sepsis
o Severe anaemia
o Hypoglycaemia
o Metabolic acidosis
o AKI
o Nephrotic syndrome
```
193
Symptoms pointing towards diagnosis in febrile traveller - jaundice?
```
Viral hepatitis
Cholangitis
Liver abscess
Leptospirosis
Typhoid
Malaria
Dengue fever
Yellow fever
```
194
Symptoms pointing towards diagnosis in febrile traveller - splenomegaly?
Malaria
| Leishmaniasis
195
Symptoms pointing towards diagnosis in febrile traveller - D&V?
```
E.coli (Travellers)
Salmonella
Shigella
Campylobacter
Vibrio cholerae
```
196
Symptoms pointing towards diagnosis in febrile traveller - hepatosplenomegaly??
Malaria
Typhoid
Brucella
197
Symptoms pointing towards diagnosis in febrile traveller - anaemia?
Hookworm
Malaria
Haemolysis
198
Symptoms pointing towards diagnosis in febrile traveller - bleeding?
Viral haemorrhagic fevers
199
Cause, incubation and spread of typhoid?
- Caused by Salmonella typhi (typhoid) and S.paratyphi (types A, B, C) (paratypod)
- Incubation – 3-21 day
- Spread – Faecal-oral route
200
Epidemiology of typhoid?
- Type A most common
| - S.typhi 10:1 S.paratyphi
201
Risk factors of typhoid?
o H2RA, PPIs – reduced stomach acidity
o Immunosuppression
o Other infections
o SCD
202
Symptoms of typhoid?
o Week One
Diarrhoea after first week
Malaise, headache, high fever, cough
Relative Bradycardia – pulse slower than expected from temperature
CNS signs (delirium, meningism, cerebellar signs, fits, coma)
Rose spots – on trunk
Epistaxis, bruising and splenomegaly
Week Two
Sustained pyrexia, high fever, malaise and weakness
Confusional state
Rose spots – crops of macules in diameter that blanch on pressure
Pea soup diarrhoea
203
Investigations of typhoid?
```
- Bloods
o LFTs raised
- Blood culture – positive for 10 days
- Stool culture
- Bone marrow aspirate
- Serology – Widal’s Test (measures agglutinating antibodies against antigens)
```
204
Management of typhoid?
- Notifiable in UK
- IV fluids
- Ciprofloxacin PO 500m BD for 10 days (Alternatives if Asia: ceftriaxone, azithromycin)
o In severe give IV ceftriaxone + ciprofloxacin
- In encephalopathy – dexamethasone
205
Testing clearance of typhoid?
o 6 consecutive negative cultures of urine + faeces
| o Treat with ciprofloxacin 500mg BD for 6 weeks if chronic carrier
206
Complications of typhoid?
```
o Osteomyelitis
o GI bleed
o Cholecystitis
o Myocarditis
o Pyelonephritis
o Meningitis
o DVT
```
207
Definition of Dengue Fever?
- Mosquito-borne viral haemorrhagic fever, transmitted by female mosquitos (Aedes aegypti)
- Most common self-limiting flu-like illness
- RNA flavivirus
208
Epidemiology of Dengue Fever?
- Endemic in Africa, Americas, Southeast Asia
| - 90% of severe dengue in <15 years old
209
Risk factors of Dengue Fever?
o High population density
o Urban living
o Poor public hygiene
o Exposure to mosquitoes
210
Symptoms of Dengue Fever?
o Flushes (neck, face, chest)
o Centrifugal maculopapular rash, progresses to confluent petechiae with pale areas of normal skin
o Headache
o Arthralgia
o Hepatosplenomegaly
o Haemorrhagic signs
Petechiae, GI/gum/nose bleeds, haematuria, menorrhagia
211
Monitoring of Dengue Fever?
o BP, urine output
o Bloods
Prolonged APTT, WCC low, platelets low
o Tourniquet Test - >20 petechiae/inch2
212
When is Dengue fever excluded?
o Symptoms start >2 weeks after leaving dengue area or if fever lasts >2 weeks, dengue ruled out
213
Management of Dengue Fever?
- IV resuscitation if needed
- Paracetamol
- Notifiable disease
214
Cause of amoebiasis?
- Caused by entamoeba histolytica
| - Spread faecal-oral route
215
Symptoms of amoebiasis?
- Ameobic dysentery:
o Starts slowly, becoming profuse and bloody
o May remit and relapse
- Amoebic colonic abscesses – may perforate causing peritonitis
```
- Amoebic liver abscess
o Single mass in right lobe containing ‘anchovy-sauce’ pus
o High-swinging fevers, sweats, RUQ pain
o Ix – High WCC, LFTs
o Dx – PCR, Liver US/CT +/- aspiration
```
216
Investigations of amoebiasis?
- Stool microscopy – trophozoites, blood, pus cells
| - Faecal antigen detection
217
Management of acute of amoebiasis?
o Metronidazole 800mg TDS PO for 5 days
| o Then diloxanide furoate 500mg TDS for 10 days to destroy gut cysts
218
Management of amoebic liver abscess?
o Tinidazole for 5 days
| o US guided aspiration if not improving
219
Definition of Traveller's Diarrhoea?
- Diarrhoea in travellers usually in first week or two of stay in foreign country
220
Epidemiology of Traveller's Diarrhoea?
- High risk – Africa, Latin America, Middle East and Asia
| - 20-60% of travellers
221
Causative organism of Traveller's Diarrhoea?
- E.coli
222
Symptoms of Traveller's Diarrhoea?
- Self-limiting diarrhoea for <72 hours usually
| - Longer than 14 days suggests Giardia, Entameoba, Cryptosporidium
223
Management of Traveller's Diarrhoea?
o Often last a few days
o Keep hydrated – ORS good
o Avoid alcohol, coffee, tea
o Loperamide/Bismuth subsalicylate used for symptomatic relief
224
Prevention of Traveller's Diarrhoea?
o Boil water if in doubt
Chlorination okay but does not kill amoebic cysts
o Avoid ice
o Avoid salads, peel your own fruit
o If cannot wash hands, discard food you are holding
o If Crohn’s or immunosuppressed – prophylactic antibiotics - ciprofloxacin
225
Definition of Lyme Disease?
- Tick-bourne infection caused by Borrelia burgdorferi
226
Epidemiology of Lyme Disease?
- Found in grassy, wooded area
| - Increase in prevalence in April-June
227
Symptoms of Lyme Disease?
o Folowing tick bite
o Erythema migrans – circular rash occurring at site of rash and can expand
Bull’s eye/Target sign appearance – centre may clear
o Fatigue, chills, fever, headache, muscle and joint pain, lymphadenopathy
228
Complications of Lyme Disease?
o Myocarditis, heart block, meningitis, neuropathy
229
Diagnosis of Lyme Disease?
- Clinical diagnosis
- If Lyme Disease suspected without erythema migrans – offer ELISA test for Lyme Disease
o If positive – perform immunoblot
230
Prevention of Lyme Disease?
o Keep limbs covered, use insect repellent
o Remove ticks using fine tweezers to grasp tick very close to skin and pull body away
o Clean with soap and water
231
Management of skin rash in Lyme Disease?
o Doxycycline 100mg BD for 21 days
| Alternative: Amoxcillin 1000mg TDS for 21 days, azithromycin 500mg for 17 days
232
Management of severe Lyme Disease?
o IV benzylpenicillin or ceftriaxone
233
Cause of cholera? Incubation and spread?
- Cause – Vibrio cholerae (Gram-negative comma-shaped flagellated mobile rods) 01 and 0139
- Incubation – few hours to 5 days
- Spread – faecal-oral route
234
Epidemiology of cholera?
- Endemic in Africa, Asia, Middle East, South America
235
Symptoms and signs of cholera?
- Profuse rice-water diarrhoea, fever, vomiting and rapid dehydration
- Sunken eyes, impaired consciousness, dry skin, reduced skin turgor, tachycardia, low BP
236
Investigations of cholera?
- Stool microscopy (+/- dark ground) and culture
- Bloods
o U&E, FBC
237
Management of cholera - general measures?
```
o Notifiable Disease
o Strict barrier measures
o Rehydration
ORS if mild
IV saline if severe
```
238
Management of cholera - Antibiotics?
o Oral erythromycin or ciprofloxacin stat may reduce fluid loss
239
Management of cholera - prevention?
```
o Good hygiene methods
o Only drink boiled or treated water
o Cook all food well, eat hot
o Avoid shellfish
o Peel all vegetables
```
240
Causes of schistosomiasis?
- Caused by blood-dwelling schistosoma worms
241
Life cycle of schistosomiasis?
o Snails release cercariae tjhat penetrate skin (during paddling), causes itchy popular rash
o Cercariae shed tails to become schistosomules, migrating via lungs to liver where they grow
o In 8 weeks, flukes mature and migrate to bladder and mesenteric veins, releasing eggs and causing granulomas and scarring
242
Symptoms of schistosomiasis?
- 2 weeks after incubation period
| o Fever, urticaria, diarrhoea, cough, wheeze, hepatosplenomegaly
243
Investigations of schistosomiasis?
- Eggs in urine or faeces
| - Antibody testing
244
Management of schistosomiasis?
- Praziquantel with food into 2 divided doses
245
Complications of schistosomiasis?
- Hydronephrosis
| - SCC of bladder
246
Antibiotic therapy used in gastroenteritis - Entamoeba histiolytica?
Mild to moderate - Metronidazole 400mg TDS for 5-10 days, followed by diloxanide 500mg TDS for 10 days
Amoebic dysentery - Metronidazole 800mg TDS for 5 days, followed by diloxanide 500mg TDS for 10 days
Alternative to Metronidazole is Tinidazole
247
Antibiotic therapy used in gastroenteritis - Campylobacter?
Consider is severe, immunocompromised, symptoms worsening or >1 week
Erythromycin 250mg-500mg QDS for 5-7 days
Ciprofloxacin 500mg BD for 5-7 days - if macrolides cannot be taken
248
Antibiotic therapy used in gastroenteritis - Cryptosporidium?
None
249
Antibiotic therapy used in gastroenteritis - Giardia Intestinalis?
Metronidazole 400mg TDS for 5 days
Tinidazole is alternative
250
Antibiotic therapy used in gastroenteritis - Salmonella & Shigella?
Consider if severe, elderly, immunocompromised, valve problems
Ciprofloxacin 500mg BD for 1 day (5 days if Shigella Dysenteriae)
Alternatives - azithromycin 500mg OD for 3 days
