Revise Notes Infectious DIsease Flashcards

Question

Lyme Disease Lyme disease can occur following infection by a group of spirochete bacteria, collectively termed Borrelia burgdorferis Transmitted to humans by Ixodes ticks - so questions may note recent history of hiking/walking etc.

Answer 1

Clinical features & Disease course The disease course is divided into 3 stages Stage 1: Early localised lyme Symptoms: Erythema migrans rash, non-specific flu-like illness Expanding, target-like rash Stage 2: Early disseminated lyme Symptoms: Multiple, small secondary erythema migrans lesions Arthritis Neurological features - meningitis, CN palsy Stage 3: Late disseminated lyme Symptoms: Lyme arthritis Neurological complications - peripheral neuropathy, encephalomyelitis

Answer 2

Complications of treatment Treatment can trigger a Jarisch-Herxheimer reaction in the first 24 hours of antibiotics (can also occur with treatment of syphilis) due to cytokine release when large numbers of bacteria are killed. Symptoms: malaise, fever & rigours, myalgia, headache, tachycardia. Self-limiting.

Answer 3

Malaria Pathophysiology Aetiology Infection of RBCs by plasmodium parasites Plasmodium falciparum - accounts for 75% of cases and the majority of deaths Non-falciparum causes: P. vivax, P. ovale Transmission: Mosquito borne - Anopheles mosquitoes Infection course Sporozoites enter bloodstream following bite and travel into liver In the liver, sporozoites mature into schizonts which rupture, releasing merozoites Merozoites infect the RBCs, where they mature and divide further Merozoites then cause the RBC to rupture which releases more merozoites to infect other RBCs.

Answer 4

Assessment of Severity (Falciparum Malaria) Malaria can be categorised as uncomplicated and complicated/severe Uncomplicated Parasitaemia < 2% with NO end organ dysfunction

Answer 5

Parasitaemia > 2% Parasitaemia < 2% but any of the following: Schizonts on the blood film Cerebral malaria - seizures/low GCS Acidosis (pH < 7.3 or Lac > 4.0) Hypoglycaemia Pulmonary oedema or ARDS Severe anaemia DIC/bleeding Shock Blackwater fever - haemolytic anaemia with resultant haemoglobinuria (dark red urine) Acute renal failure Jaundice Hb < 80

Answer 6

Uncomplicated falciparum malaria 1st line: Oral Artemisinin-based combination treatment Artemether-lumefantrine (Riamet) is drug of choice 2nd line: Quinine plus doxycycline/clindamycin If vomiting - treat as severe Severe/Complicated falciparum malaria Manage in HDU/ITU 1st line: Intravenous artesunate 2nd line: IV quinine (monitor closely for hypoglycemia)

Answer 7

Acute treatment: 1st line: Artemether-lumefantrine 2nd line: Chloroquine Prevention of Relapse (PV/PO): Primaquine 14 days Treatment of both the active infection and the liver hypnozoite stage is required for PV/PO, or relapse may occur. P. Malariae has no hypnozoite stage - can treat with chloroquine monotherapy Check G6PD levels - Primaquine can induced haemolytic crisis in G6PD deficiency

Answer 8

Epidemiology More likely if not fully immunised or no history of measles infection Most at risk- young adults MMR vaccine has reduced prevalence to 800 cases a year in UK Globally 140000 deaths a year Mortality 2%- higher in immunosupressed Clinical Features Prodromal symptoms - malaise, high fever (39+), cough, conjunctivitis Koplik’s spots are pathognomonic- 2mm red spots with white/blue centres on buccal mucosa Rash Erythematous and maculopapular Begins on face and behind ears then descends down body over 3-4 days Lasts around one week

Answer 9

Management Supportive- majority self-limiting Notifiable disease Post-exposure prophylaxis of vulnerable contacts Stay at home until at least 4 days after development of rash Complications Increased susceptibility to opportunistic infections Otitis media Pneumonia Encephalitis Subacute sclerosing panencephalitis Rare degenerative disease of CNS Seizures Decline in motor, cognitive and behavioural function Measles keratoconjunctivitis Can result in blindness

Answer 10

Pathophysiology Meningitis - inflammation of the inner layers of the meninges (pia/arachnoid mater) Aetiology Viral - enteroviruses most common (coxsackie/echovirus groups), mumps, HSV, EBV, VZV, measles etc. Bacterial Streptococcus pneumoniae (pneumococcal meningitis) Most common cause in adults Neisseria meningitidis - can present with meningitis, meningococcal septicaemia, or both MenB is the commonest causative subgroup Haemophilus influenzae b Listeria - an important cause in neonates and elderly/immunocompromised patients

Answer 11

Clinical features Symptoms Headache Photophobia/phonophobia Neck ache/stiffness Fever Seizure General malaise, myalgia, lethargy etc. Examination findings Meningism Kernig’s sign - Flex the hip and knee to 90 degrees while pt is led flat - then slowly extend their knee - if pain with extension beyond 135 degs - positive Brudzinski’s sign - flex pts neck, bringing chin to chest whilst led flat. If this causes involuntary flexion of hip and knees (relieves the stretch on meninges) - positive Non-blanching petechial or purpuric rash - suspicious of meningococcal septicaemia Signs of sepsis/shock, neurological deficit

Answer 12

Contraindications for LP Raised intracranial pressure Reduced/fluctuating consciousness Cushing’s response - bradycardia, HTN Papilloedema Focal neurology, abnormal posturing, unresponsive pupils Septic shock CR > 2s, mottled/abnormal complexion, poorly perfused extremities Hypotensive and tachycardic Reduced urine output Meningogococcal septicaemia - Spreading purpura Coagulopathy (e.g. DIC/thrombocytopenia/anticoagulants)

Answer 13

Management Patients with erythema migrans rash, but no focal symptoms (neuro/arthritis etc) Start oral antibiotics (doxycycline) If no erythema migrans (but clinically suspected), consider starting ABx, and.. Perform ELISA test for lyme If ELISA test is positive or equivocal - perform immunoblot test for Lyme If investigations are positive for lyme disease - Start oral antibiotics Antibiotics in Primary Care 1st line: Doxycycline 100mg BD for 21 days 2nd line: Amoxicillin 1g TDS for 21 days Use amox 1st line in children < 9 years If there are focal neurological, cardiac, dermatological features, or lyme arthritis, antibiotic regimens will be guided by specialist.

Answer 14

Complications of treatment Treatment can trigger a Jarisch-Herxheimer reaction in the first 24 hours of antibiotics (can also occur with treatment of syphilis) due to cytokine release when large numbers of bacteria are killed. Symptoms: malaise, fever & rigours, myalgia, headache, tachycardia. Self-limiting

Answer 15

Lumbar Puncture - Interpretation of CSF Bacteria Viral Tuberculosis Fungal Appearance Cloudy Clear Opaque, fibrin web Cloudy WCC > 100 cells/μL Primarily PMNs 10-1000 cells/μL Primarily lymphocytes 50-500 cells/μL Primarily lymphocytes 10-500 cells/μL Protein Elevated (>50mg/dL) Elevated (>50mg/dL) Elevated ++ Elevated Glucose Low (< 40% serum glucose) Normal (>60% serum glucose) Nb. can be low in HSV or mumps Low (< 40% serum glucose) Low Additional Gram stain & MCS PCR for HSV, VZV etc mZN stain for AFB, TB culture, PCR India ink (cryptococcal) Pattern recognition Polymorphonuclear neutrophils + low glucose = Bacterial meningitis Lymphocytes + normal glucose (mumps/HSV can be low) = Viral meningitis Lymphocytes + low glucose + very high protein = TB

Answer 16

Management Notifiable disease - HPU Contacts - offer MMR to any non-immunised contacts asap Conservative/symptomatic management To seek medical advice if complications develop (as above) Nb. mumps epididymo-orchitis is conservatively managed without abx/steroids. Patients should isolate and be advised to stay off school or work for 5-7 days after the development of symptoms. Patients are infectious from three days before the onset of symptoms to seven days afterwards.

Answer 17

Pathophysiology Rapidly spreading severe soft tissue infection characterized by rapid spreading of bacteria through to the deep fascia Often involves mixed aerobic and anaerobic bacteria. Epidemiology Rare but can occur at any age Risk factors: Immunocompromised especially diabetics Causes Type 1- Mix of aerobes and anaerobes. Often post-operatively in diabetics- increased if on SGLT2 inhibitor Type 2- Group A beta-haemolytic strep (strep pyogenes)

Answer 18

Acute encephalitis Acute infectious hepatitis Acute meningitis Acute poliomyelitis Anthrax Botulism Brucellosis Cholera COVID-19 Diphtheria Enteric fever (typhoid or paratyphoid fever) Food poisoning Haemolytic uraemic syndrome (HUS) Infectious bloody diarrhoea Invasive group A streptococcal disease Legionnaires’ disease Leprosy Malaria Measles Meningococcal septicaemia Monkeypox Mumps Plague Rabies Rubella Severe Acute Respiratory Syndrome (SARS) Scarlet fever Smallpox Tetanus Tuberculosis Typhus Viral haemorrhagic fever (VHF) Whooping cough Yellow fever

Answer 19

Steroids Give dexamethasone for bacterial meningitis if > 3/12 - reduces neurological sequelae Do not use if: < 3/12 Septic shock or meningogococcal septicaemia Immunocompromised Contacts No treatment required for contacts of pneumococcal meningitis Meningococcal meningitis or septicaemia Prophylactic antibiotics are indicated in those who have had prolonged close contact in household setting during 7 days preceding onset of symptoms 1st lie: PO ciprofloxacin - 500mg single dose PO for > 12 yrs age Alternative: Rifampicin

Answer 20

Decolonisation Management consists.. Skin decolonisation - chlorhexidine gluconate 4% cleansing solution (OD as bodywash and shampoo on D1/D3) - for 5 days total Nasal decolonisation - Mupirocin 2% ointment - TDS - for 5 days total

Answer 21

Leprosy (Hansen’s disease) Aetiology Mycobacterium leprae Clinical Features Skin changes - pigmentation may become lighter/hypopigmented OR darker/hyperpigmented, dry and flaky There is classically sensory loss of the affected areas of skin due to damage to sensory neurones - can cause injuries (e.g. burns) due to lack of sensation Can progress to paralysis - e.g. of hands/feet Other signs - loss of eyebrows, saddle-nose deformity, corneal ulcers causing blindness

Answer 22

Diagnosis Necrotising Fasciitis Clinical suspicion is crucial, do not wait for imaging to consider surgical management Risk stratify in borderline cases- LRINEC score Management Immediate surgical debridement of necrotic tissue Broad-spectrum antibiotics

Answer 23

Management Mild disease - doxycycline Severe - IV Benzylpenicillin or ceftriaxone

Answer 24

Examination findings Bradycardia Rose spots on trunk - blanching maculopapular lesions Hepatosplenomegaly Mild ascites Diagnosis Blood cultures Management 1st Line: cefotaxime/ceftriaxone

Answer 25

Normal GCS, normal sensation Symmetric, descending flaccid paralysis of motor neurones and autonomic nervous system Begins with cranial nerves - Dysphagia, diplopia, ptosis, dysphasia Management Botulism Antitoxin

Answer 26

Zika virus Spread through bite of Aedes mosquitos Infection during pregnancy can cause - microcephaly, teratogenesis

Answer 27

Examination findings Visible lice (crab-like, approx 1-2mm) Eggs (small, white dots) Maculae ceruleae - blue/red papules at site of lice feeding Management 1st line: Topical insecticide - Permethrin 5% or malathion 0.5% Re-examine after 1 week, and consider repeat treatment if live lice seen

Answer 28

Perianal itching is the primary complaint Classically worse at night, which disturbs sleeps May visualise small, white threads in stool/on paper etc. Can cause vulval itching in women too Investigations Adhesive tape test - sent for microscopy Management 1st line: Single dose of mebendazole May need 2nd dose after 2 weeks if persistent infection Children < 6 months and pregnant/breastfeeding women - treat with rigorous hygiene measures alone for 6 weeks Hand washing, fingernail trimming, regular changing of bed linen etc.

Answer 29

Ascaris lumbricoides Pathophysiology Cause: Ascaris lumbricoides - the largest type of roundworm found in humans One of the most common intestinal worm infections in the world Faecal-oral transmission by ingestion of eggs From the GIT, the larvae are carried to the lungs in the bloodstream. In the lungs they mature, they then ascend the bronchial tree into the oropharynx, where they are swallowed back into the GIT.

Answer 30

Clinical features History of recent travel/migrants from endemic areas Often asymptomatic / mild, non-specific symptoms if low worm burden Symptoms may include: If significant worm burden - abdominal pain, distension, N&V, change in bowel habit, malabsorption. Loeffler’s syndrome - eosinophilic pneumonitis - inflammatory reaction vs the larvae which migrate into the lungs as above. Symptoms: Cough, wheeze, fever, SOB +/- haemoptysis Rash - urticarial rash as reaction to migrating larvae in the skin Investigations Stool for ova, cysts and parasites FBC might show eosinophilia Management 1st line: Single dose of mebendazole Nb. unlicensed if pregnant/breastfeeding or < 2 yrs

Answer 31

Examination findings Bimanual exam - adnexal tenderness, cervical excitation/motion tenderness SIRS, pyrexia Investigations Clinical assessment Pregnancy test Test for causative organisms - CT/NG/MG (Nb. negative tests do not exclude PID) Bloods - elevated inflammatory markers The absence of endocervical/vaginal pus cells has a negative predictive value of 95% (but poor PPV), so is useful to r/o PID

Answer 32

Management BASHH recommend a low threshold for empiric treatment due to (i) lack of definitive diagnostic criteria and (ii) risk of long-term sequelae with delayed treatment (ectopic/infertility). Outpatient antibiotic regimens IM ceftriaxone 1g stat + PO doxycycline 100mg BD + PO metronidazole 400mg BD for 14 days PO ofloxacin + metronidazole for 14 days PO moxifloxacin for 14 days Inpatient antibiotic regimens IV ceftriaxone + IV doxycycline (followed by PO metronidazole + doxycycline) IV clindamycin + IV gentamicin (followed by PO clindamycin + metronidazole

Answer 33

Clinical Features Incubation period 14-21 days Rash 14-17 days post-exposure Starts on face/neck then becoming generalised Pink/light-red, discrete, maculopapular Mild itch Lasts 3-4 days Lymphadenopathy Arthritis/arthalgia Non-specific viral symptoms (fever, malaise) Rare: Thrombocytopenia Encephalitis Serious complications especially in pregnancy: Congenital rubella syndrome Highest risk in first trimester (8-10 weeks gestation 90% risk) No reported cases beyond 20 weeks gestation Eye defects (cataracts), hearing impairment, cardiac (patent ductus arteriosus), microcephaly, developmental delay, autism, intra-uterine growth restriction

Answer 34

Management Remain infectious from 7 days before symptoms to 4-10 days after onset of rash Most infectious when rash erupting Notifiable disease Specific Non-pregnant Supportive measures Most symptoms self-resolve within a week Avoid contact with pregnant women Pregnant Urgent referral to obstetrics- risk assessment and counselling Supportive and contact avoidance as above No specific treatment for congential rubella syndrome

Answer 35

Clinical features: Symptoms Pruritic papular rash - termed swimmer's itch following freshwater exposure A history of swimming especially in freshwater/with travel is a big clue. Fever, malaise, and eosinophilia. Acute Phase: Katayama fever - fever, chills, myalgia, lymphadenopathy, hepatosplenomegaly, and diarrhoea. Chronic infection: Symptoms vary based on species S. haematobium - hematuria, dysuria. Can cause bladder squamous cell carcinoma. S. mansoni and S. japonicum - gastrointestinal symptoms, liver cirrhosis. Examination findings Hepatosplenomegaly, signs of CLD - ascites, portal hypertension.

Answer 36

Management Praziquantel - 1st line The treatment of schistosomiasisis with an antiparasitic medication called praziquantel. Effective against all species of Schistosoma. Treatment involves a short course, usually administered as a single dose or over one to two days, depending on the severity and species.

Answer 37

Management- Sepsis 6 bundle within one hour of recognition of sepsis Take blood cultures Check lactate Check urine output/fluid balance Give oxygen to ensure saturation > 94% Give IV fluid bolus Give broad spectrum antibiotics

Answer 38

Epidemiology Underlying cause or contributing factor to 25000 deaths a year in UK Mortality 25% - increases with delayed diagnosis and lack of prompt management Septic shock mortality- 50% Risk factors Age extremes- < 1 year and > 75 years Frailty Drug abuse including alcohol Recent trauma or surgery Breach of skin including burns, ulcers or indwelling lines Pregnant or post-partum < 6 weeks Immunocompromised Due to underlying condition e.g. HIV, diabetes mellitus, sickle cell, spleen disorders Due to drug treatment e.g. systemic anticancer therapy, steroids, other immunosuppressive drugs

Answer 39

Clinical Features Can be non-specific Malaise Agitation Confusion Fever or hypothermia Specific to infection site, for example: Hypoxic and tachypnoea - respiratory source Dysuria, reduced urine output- urinary source Abdominal pain, vomiting, distension- gastrointestinal source Rash and confusion- meningococcal disease

Answer 40

Examination findings GCS- new lower GCS Fever- most common finding Tachycardia Tachypnoea Hypotension Raised capillary refill time Reduced oxygen saturations Skin changes- mottled, pale, cyanosis, cold

Answer 41

Complications Organ dysfunction including: Acute kidney injury Acute respiratory distress syndrome Congestive cardiac failure Liver failure Recurrent and secondary infection i.e. hospital acquired Coagulopathy causing VTE or disseminated intravascular coagulation (DIC) Psychological trauma from long hospital stay

Answer 42

Abnormality of vaginal flora - overgrowth of anaerobic organisms and depletion of lactobacilli Vaginal pH is normally acidic - but becomes more alkaline, with pH > 4.5 Not sexually transmitted, but more prevalent amongst sexually active individuals Significance: BV is associated with complications including misscarriage, preterm labour, PROM, postpartum infections. Clinical features Vaginal discharge (VD) - BV is the most common cause of abnormal VD in women of child-bearing age Characteristically, a thin, grey/white discharge which smells “fishy” There is not normally vaginal pruritus/pain

Answer 43

Amsel criteria The presence of three out of the following 4 indicates a diagnosis of BV: Vaginal pH > 4.5 Positive whiff test - release of a ‘fishy’ odour, with addition of 10% KOH Clue cells > 20% total cell population Characteristic discharge - thin, homogenous Management 1st line: Oral metronidazole 400mg BD for 1 week Alt: If poor compliance - 2g metronidazole stat dose (not if pregnant)

Answer 44

Clinical Features Women 50% asymptomatic Vaginal discharge Variable, but classically described as frothy, yellowy-green Vaginal/vulval pruritus Dysuria Speculum examination: Strawberry cervix, inflammation of vulva/vagina Visible, punctate macular haemorrhages on cervix gives strawberry-like appearance Men: Urethritis - urethral discharge, dysuria, frequency Rarely - symptoms of prostatitis Management 1st line: Oral metronidazole 400mg BD for 1 week Alt: If poor compliance - 2g metronidazole stat dose (not if pregnant) Treat any partners within the last week too.

Answer 45

Clinical features Vulvovaginitis - itching, soreness Dysuria Vaginal discharge - thick, white ‘curd’ or ‘cheese’ like vaginal discharge Management 1st line: Stat dose of oral fluconazole 150mg Contraindications: Pregnant or breastfeeding 2nd line: Stat dose of clotrimazole 500mg as intravaginal pessary Consider co-prescribing topical clotrimazole cream if vulval symptoms

Answer 46

Oral candidiasis Clinical features Patches of white/yellow plaque on the tongue, cheeks or palate Dysphagia Management: 1st line: Miconazole oral gel 2nd line: Nystatin suspension If severe: Fluconazole 50mg OD for 14 days

Answer 47

Investigations PCR testing of viral swab taken from base of ruptured vesicle Management Conservative measures: Saline bathing, OTC analgesia Topical lidocaine 5% may help with dysuria Antivirals: First episode: Prescribe oral antivirals (NOT topical) within 5 days of first episode/while new lesions forming 1st line: Aciclovir/ Valaciclovir for 5-10 days Recurrent episodes: Two options depending on frequency. Episodic Tx: If episodes are infrequent (<6/year) - offer a course of antivirals for each episode. Suppressive Tx: If 6 or more episodes per year - offer regular PO antivirals Prescribe for one year max, before reassessment of episode frequency - can continue Tx if episode frequency remains high If first episode of genital herpes during pregnancy, there is a risk of neonatal herpes (highest risk in 3rd trimester) - refer for specialist advice

Answer 48

Transmitted by contact with infected secretions at mucosal surfaces. Primary infection - initial infection with HSV. Patients are often asymptomatic. Primary infection is followed by viral latency (HSV remains dormant within sensory ganglia) Recurrent herpes - the presence of symptoms, due to the reactivation of HSV.

Answer 49

Clinical features Urethral discharge Dysuria Posthitis Balanitis Investigations Investigate for underlying STI including Chlamydia + Gonorrhoea - first-void urine (FVU) sample for NAAT Mycoplasma genitalium Trichomoniasis - urethral swab/FVU for MCS

Answer 50

Management Offer empirical ABx for chlamydial infection - doxycycline 100mg BD 7/7 Alt: Azithromycin Consider treating for gonococcal/trichomoniasis as above if suspected Ciprofloxacin/ceftriaxone or metronidazole respectively

Answer 51

Gonorrhoea Pathophysiology Cause: Neisseria gonorrhoea (Gm -ve bacteria) Complications: Epididymo-orchitis, prostatitis, PID, infertility Clinical features Most commonly causes an uncomplicated, lower genital tract infection. Women: Urethritis - dysuria Endocervical infection Abnormal vaginal discharge Lower abdominal pain Intermenstrual bleeding Deep dyspareunia Men: Urethritis - mucopurulent discharge, dysuria Symptoms 2-7 days post exposure

Answer 52

Management 1st Line: Doxycycline 100mg BD for 1 week 2nd line: Azithromycin 1g PO stat dose, then 500mg PO OD for 2 days This is also the 1st line in pregnancy Test of cure not routinely indicated, unless poor compliance/pregnant Can offer repeat test in 6 months to check for re-infection Pregnant/ breastfeeding women: Tetracyclines contraindicated 1st Line: Azithromcyin, erythromycin or amoxicillin Test of cure is indicated in pregnancy Complications Fitz-Hugh-Curtis syndrome - perihepatitis secondary to CT - presents with RUQ pain +/- referred shoulder pain Reactive arthritis Epididymo-orchitis Pelvic inflammatory disease

Answer 53

Clinical features Commonly asymptomatic - half of men and three quarters of women! Women: Vaginal discharge which may be thick, cloudy, may be yellow in colour, may be malodorous Dysuria Deep dyspareunia Post-coital bleeding Intermenstrual bleeding Pelvic pain, tenderness O/E: Cervical motion tenderness, inflamed cervix +/- contact bleeding Men: Dysuria White, cloudy discharge Lymphogranuloma venereum Cause: Chlamydia trachomatis serovars L1, L2, L3 An ulcerative disease of the genital area which is most common in men who have sex with men (MSM). Symptoms occur in 3 stages: Stage 1: PAINLESS genital ulcers/papules Symptoms include bloody anorectal discharge, tenesmus Stage 2: Tender inguinal lymphadenopathy Stage 3: Strictures/fibrosis/fistulae of anogenital area

Answer 54

Pathophysiology Occur when bacteria contaminate the surgical wound, leading to local inflammation and tissue damage Most common organisms include: Staphylococcus aureus Coagulase-negative Staphylococcus Pseudomonas Escherichia coli Risk factors Prolonged emergency surgery (> 2 hours) Contaminated or dirty wounds Pre-existing medical conditions- diabetes, immunosuppressive disorders or medications Smoking

Answer 55

Management Conservative: Wound care Intravenous antibiotics Surgical intervention if above fails or concern regarding deep infection: Wound debridement Drainage of abscesses Removal of infected implants Complications Delayed wound healing Abscess formation Cellulitis Sepsis and systemic infection

Answer 56

The disease course is divided into early syphilis and late syphilis. Early syphilis is further categorised into primary, secondary and early latent Primary syphilis Characterised by a chancre - a single firm, indurated ulcer, often associated with regional lymphadenopathy. The ulcer is usually PAINLESS, with well-defined margins Secondary syphilis - systemic features including: Generalised lymphadenopathy Systemic upset - fever, lethargy etc. Snail tract lesions on oral mucosa Condylomata lata - wart-like lesions Maculopapular rash - usually generalised, but may only affect the soles of the feet/palms of the hands - often rough, red/brown spots. Early latent - Confirmed infection but currently asymptomatic

Answer 57

Late syphilis (after > 2 years of infection) Late latent infection Tertiary syphilis - uncommon, but characterised by complications such as: Neurosyphilis, inc. tabes dorsalis, general paralysis of the insane (dementia) Gumma - locally destructive nodules/plaques Aortitis with subsequent aneurysm or aortic regurgitation

Answer 58

Investigations Assessment is complex and should be led by GUM specialists. It involves a combination of the following: Direct tests for syphilis - swabs taken from primary lesion sent for PCR or studied under dark-field microscopy - demonstrate the presence of treponema pallidum. Serological tests: Treponemal tests Examples: EIA, CLIA Detect treponemal IgG and IgM (but cannot differentiate between other, non-venereal types of treponemal infection) NOT useful for monitoring Tx response, as IgG/IgM levels remain +ve lifelong in most people Non-treponemal tests Examples: VDRL antigen test/ RPR Can be used to monitor effect of Tx (with successful Tx, RPR titre declines by fourfold after 6 months)

Answer 59

Management 1st Line: IM Benzathine Benzylpenicillin Complications Complications of treatment - Jarisch-Herxheimer reaction An acute illness which occurs in response to treatment Symptoms: Fever with rigors, headache, general malaise, myalgia, tachycardia - resolves after 24hrs Differentiate from anaphylaxis, as no wheeze/hypotension. Self-limiting - supportive treatment only. Argyll-Robertson Pupils Small irregular pupils with absent pupillary reflex ARP - PRA - pupillary reflex absent Causes: Syphilis, diabetes

Answer 60

Clinical features 1. A history of risk factors Birth in high prevalence area (> 40 cases/100,000 population) India, Pakistan, Romania, Somalia, Eritrea - highest risk Immunosuppression - HIV, DM, ESRF, malignancy, drugs Living circumstances - homeless shelters, prisons 2. Systemic symptoms of TB Weight loss Fever Night sweats General malaise, lethargy, anorexia 3. System-specific symptoms of TB Symptoms of pulmonary involvement - cough +/- haemoptysis Symptoms of extrapulmonary involvement: Lymphadenopathy, often cervical, supraclavicular - lymphatic TB Bone pain - skeletal TB Abdominal pain - GI/GU TB Urinary symptoms/sterile pyuria - renal TB TB Meningitis Cutaneous TB - erythema nodosum, lupus vulgaris, scarring alopecia Nb. Lupus vulgaris is the most common manifestation of dermatological TB Erythematous flat plaques, which evolve and become painful, ulcerated nodular lesions Most commonly affect the face, nose, mouth

Answer 61

Investigations Active TB Suspected Pulmonary TB CXR - bilateral hilar lymphadenopathy, upper lobe fibrosis/cavitation Sputum samples Arrange 3 x early morning sputum samples - for microscopy with ZN staining for acid-fast bacilli and culture Suspected Extra-pulmonary TB CXR Respiratory sample as above Further investigations depend on site of suspicion - x-rays, US, urine samples, echo, CT scans, LP etc

Answer 62

Latent TB Patients who are asymptomatic, but considered at high risk of infection should be screened. This includes: Patients with contact with a person diagnosed with active TB (e.g. partner/household member) Immunocompromised patients: HIV, organ transplant High-prevalence groups - prisons/homeless shelters Immigrants from high prevalence countries New NHS employees

Answer 63

Mantoux test Intradermal tuberculin injection After 2-3 days review the induration If < 5mm = negative 5mm induration or more = positive False negatives can occur in HIV, lymphoma, sarcoidosis, miliary TB, age < 6/12 IGRA test - interferon-gamma release assay Blood test - measure the quantity of IFN-gamma produced in response to M TB antigens

Answer 64

Rifampicin A potent liver enzyme inducer (pcbRas) Hepatitis Orange secretions/urine Isoniazid Peripheral neuropathy (reduce risk with pyridoxine co-prescription) Agranulocytosis Pyrazinamide Hyperuricemia - Gout Ethambutol Optic neuropathy (check visual acuity before treatment) Bilateral painless, symmetric loss of colour vision and central visual acuity

Answer 65

Initial phase - 2 months - RIPE Rifampicin Isoniazid (with pyridoxine cover) Pyrazinamide Ethambutol Consolidation phase - 4 months - RI Rifampicin Isoniazid (with pyridoxine cover) CNS TB (e.g. TB meningitis) Prolonged treatment regimen (12 months) Also require steroids for 1-2 mont

Answer 66

Treatment of Latent TB Options include.. 3 months of Rifampicin and Isoniazid (with pyridoxine cover).. OR Best for patients < 35 yrs - at low risk of hepatotoxicity 6 months of Isoniazid monotherapy (with pyridoxine cover) Best for patients at risk of rifampicin drug interactions (inducer)

Answer 67

Facial flushing/erythema, or injected oropharynx in first 24-48 hours Maculopapular rash Fever - commonly biphasic Headache with retro-orbital eye pain Haemorrhagic manifestations - petechial rash, bruising, positive tourniquet test, bleeding gums, haematuria Severe dengue - increased vascular permeability - pleural effusions, ascites, then shock and multiorgan failure, severe haemorrhage. Bloods Thrombocytopenia, leukopenia, lymphopenia

Answer 68

Sudden onset of fever, rigours, flu-like symptoms Bradycardia Most will recover within one week However approx. 15% of infected patients develop severe disease, after a brief period of apparent remission, characterised by: Jaundice Haematemesis Acute renal failure - oliguria

Answer 69

Overview Viral haemorrhagic fevers (VHFs) are a group of viral illnesses characterised by bleeding/haemorrhage. Clinical features Abdominal pain Flu-like symptoms - malaise, lethargy, headache Haemorrhage - Bloody diarrhoea, petecihal rash, bruising/DIC, haematemesis Multi-organ failure

Answer 70

Subtypes and clinical features Common wart Rough, raised, cauliflower-like papules with a hyperkeratotic surface Plantar wart (verrucae) Warts growing on the palms of the hand/soles of the feet. Can be painful Central dark spots (capillary thrombosis) Can be inwardly growing Filiform wart A narrow pedicular base, with a cluster of ‘finger-like’ extensions/fronds Often occur on the face