Infectious Disease Flashcards
Name 3 causes subtle convulsions in severe malaria
- Hypoglycaemic
- cerebral malaria
- pyrexia
Which drug is used to treat severe malaria
Intravenous artesunate
Alternative: iv quinine
What causes Katayama’s disease?
Schistosoma japonicum
Which 3 parameters are used to classify pneumonia if little access to diagnostic technology?
- Respiratory rate
- chest indrawing
- General danger signs
Treatment amebiasis?
Metronidazole
Treatment bilharzia?
Praziquantel
Treatment ascaris lumbricoidis?
Mebendazole
Treatment Candida albicans?
Amphotericin B
Which condition is associated with paediatric COVID 19?
PIMS: paediatric inflammatory multisystem syndrome
Which empirical antibiotic should be given for dysentery and why?
Iv ceftriaxone for 5 days
Most probably S Typhi, which is resistant to penicillins
Describe the stages and progression of syphilis (5)
Early syphilis: infections
- primary syphilis
→ incubation 17 - 28 days
→ chancre → 1 week → lymph nodes
- secondary syphilis
- early latent phase
Late syphilis: non-infections
- Late latent phase
- tertiary syphilis
Describe the symptoms and RPR title of early syphilis (9)
Primary
- Incubation 17-28 days ; RPR negative
- chancre: painless, may be multiple
- 1 week asymptomatic
- lymph nodes: painless, bilateral, if on cervix then no inguinal lymph nodes
- RPR 1:4
Secondary
- skin lesions eg condylomata lata
- RPR 1:8 and higher (peaks)
Early latent phase (about 1 year)
- asymptomatic
- RPR positive but starting to decrease
Describe the symptoms and RPR title of late syphilis (4)
Late latent phase (about 1 year)
- asymptomatic
- Rpr negative
- Tpha positive
Tertiary syphilis
- other systems affected eg CNS, CVS
- once positive the tpha test remains positive for life whether treated or not
Name 8 signs congenital syphilis
- desquamative rash (red/blue spots or bruising esp on soles and palms )
- jaundice
- pallor
- distended abdomen due to enlarged liver/spleen
- low birth weight
- respiratory distress
- pale placenta
- hypoglycaemia
Treatment asymptomatic newborn infant in mother with syphilis
Benzathine penicillin (pen G) 50 000 u/kg IM stat only if
- mom wasn’t treated
- mom received <3 doses benzathine Benzylpenicillin
- Mom delivers within 4 weeks of starting treatment
Treatment symptomatic newborn infant in mother with syphilis
- refer
- procaine penicillin. 50 000 u/kg IM daily 10 days, or benzyl penicillin G 50 000 u/kg/dose 12 hourly intravenously 10 days
- erythromycin not reliable
Diagnosis strep pneumonia?
Cultures! NOT from nasopharynx
Treatment strep pneumonia URTI
Amoxil
Treatment strep pneumonia meningitis
3rd generation cephalosporin
Eg ceftriaxone
Clinical features and complications corynebacterium diphtheria (9)
- sore throat, fever, toxaemia
- white grey membrane in nose/oropharynx - attempt to remove → bleeding
- Bull neck: cervical lymphadenopathy and periadenitis
- myocarditis
- neuritis: palatal and pharyngeal, ocular muscles, intercostal, peripheral nerves
Complications
- pneumonia
- thrombocytopenia, DIC
- renal failure
- airway obstruction
Management corynebacterium diphtheria (3)
- Penicillin 10 days
- Airway
- Antitoxin
Classical Clinical features and stages Bordetella pertussis (5)
- Whooping cough!
- incubation 3 days
- catarrhal stage 1-2 weeks
- paroxysmal stage
- Convalescent stage
More recent Clinical features Bordetella pertussis in infants <6 months (7)
- Short catarrhal stage
- gagging
- gasping
- apnoea
- absence of whoop
- Prolonged convalescence
- sudden unexpected death
Complications: pneumonia, seizures, encephalopathy
Disease of infancy: no transplacental immunity
Management Bordetella pertussis (2)
- Hospitalize, oxygen during spells
- azithromycin/clarithromycin
Treatment salmonella enterica typhi ( 2)
- ceftriaxone
- ciprofloxacin
(Resistance to ampicillin and chloramphenicol)
Name 8 clinical features congenital syphilis (treponema pallidum)
- Skin: bullae, desquamation, red maculo- papules, condylomata
- mucous membranes: fissures, scars, rhinitis
- liver/spleen: hepatosplenomegaly, jaundice, hepatitis
- haematological: anemia, leukaemoid reaction, thrombocytopenia, DIC
- bones: metaphysitis, periostitis, diaphysitis
- CNS: meningo encephalitis, convulsions, hydrocephalus
- renal: nephrosis
- other: sga , pneumonia alba, chorio-retinitis
Diagnosis syphilis (3)
Non-specific: vdrl, RPR
Specific: FTA IG M - may only become positive after 3 months
Treatment syphilis (treponema pallidum) with meningeal involvement
Pen G for 10 days
Define poliomyelitis
Any case Of acute flaccid paralysis including guillan barre that is not caused by injury in child < 15
Describe the 3 categories of rabies and treatment
Category 1: touching/feeding animal but skin intact (wound cleansing)
Category 2: minor scratches without bleeding; nibbling of uncovered skin (vaccine)
Category 3: bites /scratches that penetrate skin and draw blood; lick eyes / mouth, lick broken skin (vaccine and immunoglobulin)
Name 9 indications to defer art commencement
- Tb symptoms - investigate and treat Tb first
- diagnose drug sensitive Tb at non-neurological site
→ if CD4 < 50: initiate art within 2 weeks of starting Tb treatment, and symptoms improving, and Tb treatment tolerated
→ CD4 50 or more: initiate art 8 weeks after start Tb treatment - diagnose drug resistant Tb at non -neurological site: initiate art within 2 weeks of starting Tb treatment, and symptoms improving, and Tb treatment tolerated
- diagnose drug sensitive or resistant Tb at neurological site: defer 4-8 weeks after start Tb treat
- signs and symptoms meningitis: investigate
- cryptococcal antigen positive in absence symptoms/signs meningitis: defer until first 2 weeks of fluconazole prophylaxis completed
- confirmed cryptococcal meningitis: defer until 4-6 weeks of antifungal treatment completed
- other acute illnesses eg pneumocystis jirovecii pneumonia or bacterial pneumonia: defer for 1-2 weeks after stunting treatment
- clinical symptoms/signs liver disease: confirm using alt and bilirubin. alt > 120 with symptoms hepatitis, and or total serum bilirubin >40 significant. Investigate.
Baseline clinical evaluation with art commencement? (10)
- Recognise respiratory, neurological or abdominal danger signs (opportunistic infections) needing urgent care
- nutritional assessment
- screen for Tb
- screen for meningitis: symptoms headache, confusion, visual disturbances, fever, neck stiff, coma.
- Screen for depression, mental health issues, substance abuse (efv and DTG have neuropsychiatric side effects)
- screen for major non-communicable chronic diseases (metformin and anti-epileptics interact with art)
- screen for pregnancy and, plans to conceive
- screen for STI
- neurodevelopmental screen
- WHO clinical stage
Baseline lab evaluation with art commencement? (8)
- Confirm HIV result
- CD4 count
- if use TDF: creatinine and egFR
- haemoglobin (azt cause anemia)
- genexpert to diagnose Tb only if symptomatic
- cryptococcal antigen test if Cd4 < 100 (if positive, do lp and give fluconazole )
- Cervical cancer screening every 3 years
- hbsag (caution TDF if positive - hepatitis flares)
When should cotrimoxazale be started and stopped in HIV positive infant <1 year old
All children should be on it irrespective on CD4 or clinical stage
When should cotrimoxazale be started and stopped in HIV positive child 1-5 years old (3)
Start:
- CD4 25% or less
- WHO stages 2-4
Stop:
- CD4 > 25% regardless of clinical stage
When should cotrimoxazale be started and stopped in HIV positive child < 5 years old with PJP
Start
After PJP treatment completed
Stop
Continue until 5 years old and stop only if CD4 criteria in older than 5 category are met
When should cotrimoxazale be started and stopped in HIV positive child >5 years old (3)
Start
- CD4 200 cells/ ul or less
- who stages 2-4
Stop
- CD4 > 200 regardless of clinical stage
Dolutegravir class?
Integrase inhibitor
Dolutegravir dose?
50 mg daily in children 20 kg or more and adolescents
If on concomitant Tb treatment, double dose to 50 mg 12 hourly
Name 5 side effects dolutegravir
Usually mild and self limiting
- insomnia
- headache
- CNS effects: depression
- gastrointestinal: increase serum creatinine
- weight gain
- neural tube defects: avoid preconception and first 6 weeks pregnancy
Benefits using DTG instead of EFV? (3)
- High genetic barrier to resistance
- no interaction with hormonal contraceptives
- side effects mild and uncommon (efavirenz neuropsychiatric, )
Benefits using efavirenz instead of dolutegravir? (3)
- safe in pregnancy
- no significant interaction with Tb treatment (dtg interact with rifampin)
- better for obese patients (dolutegravir: weight gain)
Name 4 drug interactions with dolutegravir
- Rifampin: Decrease dolutegravir concentrations (double dose)
- polyvalent cations - mg, fe, ca, al, zinc eg antacids, sucralfate, multivitamin, nutritional supplements: Decrease dolutegravir concentrations
- anticonvulsants - carbamazepine, phenytoin, phenobarbital: Decrease dolutegravir concentrations
- metformin: increase metformin levels
How should polyvalent cations be taken with dolutegravir (4)
- Take calcium and DTG together with food (only decrease DTG on empty stomach)
- take iron with DTG with food
- calcium and Ir on must be taken at least 4 hours apart
- magnesium/aliminium containing antacids should be taken minimum 2 hours after or 6 hours before DTG
Which anticonvulsants can be used with DTG (4)
- Valproate
- lamotrigine
- Levetiracetam
- topirimate
If carbamazepine must be used, double DTG to 50 mg 12 hourly
First line art in adolescents at least 35 kg and at least 10 years old
TLD
Tee (efavirenz, emtricitabine, tenofovir) if pregnant up to 6 weeks/ want to conceive soon
First line art in neonates (birth - 4 weeks) weighing at least 2,5 kg
Azt + 3TC+ NvP
LAN
First line art in infants and children (more than 4 weeks age and 42 weeks or more gestational age ) weighing at least 3 kg
ABC + 3TC+ lpv/r
All
First line art in children <10 years or weighing 20-35 kg
ABC + 3TC + dtG
Lad
Transition from lpv/r in infanthood to dtg requires vl < 50 in last 6 months
First line art in children > 10 years and weighing >35 kg
TLD
Transition from childhood art requires vl < 50 in last 6 months. Make sure renal function is fine
Name 3 art drugs that interact with rifampin and how to manage
- Nevirapine ( taken by neonates, seek expert advice)
- LPV /r ( taken by infants and children < 20kg): double dose tablets or give additional ritonavor solution or powder.
- DTG: double dose
Continue boosting art until 2 weeks after stopping rifampicin
Routine vl monitoring for patients on art? (3)
- 6 months after starting art
- if suppressed (<50) repeat at 12 months (otherwise in 3 months)
- 12 monthly therafter
Routine Cd4 monitoring for patients on art? (3)
- Month 12 on art
- every 6 months until meet criteria to discontinue CPT
- stop if vl < 1000
- if > 1000, every 6 months
Management of raised viral load in children on art? (4)
Do thorough assessment of cause: ABCDe (adherence, bugs, in correct dose, drug interaction, rEsistance ) implement interventions to resuppress vl including enhanced adherence support and repeat after 3 months
- 50 - 999 → continue enhanced adherence support and repeat in 6 months
- 1000 or more
→ on NNRTI ( efv/ nvp) based regimen: consider switching to second line if confirmed virological failure (1000 or more on 2 consecutive occasions and adherence issues addressed )
→ on insti (dtg) or pi based regimen: consider second line confirmed virological failure (vl 1000 or more on at least 3 occasions over the last 2 years; or 1000 or more with signs of immunological or clinical failure ie declining CD4 and / or opportunistic infections )
Name side effect abacavir
Hypersensitivity (fever, rash, git, resp) in first 6 weeks
Symptoms typically worsen in hours immediately after dose
If occurs, stop permanently.
Name side effect lamivudine
Generally well tolerated. Rarely pure red cell aplasia causing anaemia
Name contraindication zidovudine
Anaemia (hb < 8): cause bone marrow suppression
Name 3 indications second line art
- Virological failure
- immunological failure
- clinical progression (opportunistic infections)
Treatment tonsillitis and pharyngitis? Why?
- Amoxycillin 25 mg/ kg twice daily for 10 days
Scared of rheumatic fever.
Name 2 causes purulent otorrhoea
- Otitis externa
- otitis media with perforation or drainage through tympanostomy (grommet)
Name 2 causes otorrhoea with clear fluid
- Serous middle ear effusion
- CSF leak
Why do younger children get otitis media?
Eustacian tube short, smaller calibre, more horizontal.
Immunologically naïve and immature
Why / how do children get otitis media? (2)
- Viral URTI > 90%
- colonization nasopharynx with pathogens
Name 6 usual causes (organisms) otitis media
Viruses
- Rsv
- Rhinovirus
- influenza
Bacteria
- strep pneumonia
- non typable haemophilus influenza
- moraxella catarrhalis
Name 3 diagnostic criteria for acute otitis media
- acute onset
- signs middle ear effusion: bulging tympanic membrane, limited or absent mobility tm, air fluid level behind Tm, otorrhoea
- signs and symptoms middle ear inflammation: distinct erythema of TM (NB in crying children this is normal), distinct otalgia (clearly preferable to ear, interfere with normal activity or sleep)
Treatment acute otitis media? Which age groups do you treat? (4)
< 6 months
- antibacterial whether sure of diagnosis or not
6 months - 2 years
- certain diagnosis: antibacterial
- uncertain: antibacterial if severe ( moderate - severe otalgia or fever 39 or more), observation if not (mild otalgia and fever <39 in previous 24 hours)
> / = 2 years
- Certain : antibacterial if severe, observation if not
- uncertain: observe (follow up)
Treat with amoxicillin 80 - 90 mg/kg/day
Name 3 bacterial causes sinusitis
- s pneumonia
- M catarrhalis
- H influenza
Name 5 predisposing factors to acute bacterial sinusitis
- Viral URTI (bacterial superinfection)
- day care
- allergic rhinitis
- anatomic obstruction
- irritants: smoke
Name 4 symptoms and 3 signs acute bacterial sinusitis
Symptoms
- Discharge
- nasal obstruction
- cough
- fever
Signs,
- discharge nasal/posterior pharynx
- sinus tenderness (rare in children)
- periorbital swelling
Treatment acute bacterial sinusitis (2)
- Amoxicillin with or without clavulanate 90 mg/kg/day at least 10 days
(If hospitalised, 3rd generation cephalosporin) - adjunctive: saline irrigation
WHO classification and treatment pneumonia in children 2 months - 5 years with cough and or difficulty breathing (3)
- cough and cold: no pneumonia (home care)
- fast breathing and/or chest indrawing = pneumonia (oral amoxicillin clavulanic acid, home care, follow up)
- General danger sign = severe pneumonia/disease (give first dose antibiotic, refer for injectable antibiotic and supportive therapy oxygen, blood transfusion, hydration, airway obstruction, temp control )
Name 3 “constitutional” symptoms measles
- Koplik spots
- descending erythematous maculopapular rash starting on face → trunk → limbs, later staining and desquamation
- barking seal cough (croup)
Name 10 complications measles!
Pulmonary
- Mostly pneumonia: bacterial superinfection or viral (measles, adenovirus, herpes); later bronchiolitis obliterans or bronchiectasis
- laryngotracheobronchitis
General
- immune suppression
Neurological
- Acute encephalitis
- encephalopathy
- sspe
Abdomen
- diarrhoea
Head and neck
- corneal ulceration!
- herpes simplex gingivostomatitis
- otitis media
What disease does parvovirus B19 cause?
Erythema infectiosum /slapped cheek disease
Erythematous rash
Name 3 populations in which parvovirus B19 is important to consider
- Haemolytic anaemia: can cause aplastic crisis
- HIV: chronic anaemia
- foetus: severe anemia and hydrops
What disease does HHV 6 cause?
Roseola infantum or undifferentiated febrile illness without rash
Erythematous rash
Name characteristic features roseola infantum
- Fever 3-7 days
- around day 3-4, characteristic erythematous rash
Also enlarged lymph nodes
What causes German measles
Virus!
Rubella.
( erythematous rash)
Cause hand foot and mouth disease?
Enteroviruses: coxsackie A 16, ev 71
Classical triad tick bite fever? Cause of disease?
- Fever
- eschar
- erythematons rash
Cause: boutonneuse fever-like TBF (r conorii), African TBF (r. Africae)
Differential diagnosis erythematous maculopopular rashes? (7)
Bacterial
- measles! (Spread downwards)
- Lyme disease (borrelia burgdorferi)
- tick bite fever (rickettsia)
Viral
- Parvovirus B 19
- HHV6! (And 7) - roseola infantum
- German measles (rubella)
- Enterovirus eg coxsackie,! ( hand foot and mouth)
Differential diagnosis vesicular and blistering rashes? (3)
Viral
- Varicella (chicken pox)!
- herpes simplex!
Bacterial
-Impetigo (staph, strep)
Treatment chickenpox?
(Varicella virus)
- healthy 12 years or less: none
- Immuno competent children 13 or older; or secondary cases in household contacts: oral antiviral therapy
Name 5 clinical features herpes simplex
- GingiVostomatitis: fever, salivation, refusal to eat; vesicles → rupture → shallow ulcers with red margin; 4-9 days
- meningo-encephalitis
- conjunctivitis
- Recurrent disease: fever blisters
- Disseminated disease: immunocompromised
Differential diagnosis petechial/ purpuric rashes
Bacterial
- meningococcus!
- gonococcus
Clinical features meningococcal disease? (5)
Variable! Ranges asymptomatic transient bacteraemia to deadly fulminant sepsis
Early: signs URTI, fever, headache, lethargy, vomiting, myalgia, joint pain
Typical:
- Urti
- fever
- haemorrhagic rash and purport
- circulatory collapse, shock
Treatment purpuric rash?
Always suspect meningococcus so treat for that.
- ceftriaxone/cefotaxime/ penicillin (if allergy: chloramphenicol
Chemoprophylaxis meningococcal meningitis?
Rifampicin to household contacts only
Name 7 important differentials for CNs infections
Virus
- enterovirus
- mumps
- HSV
Bacteria
- meningococcal meningitis
- N meningitides
- s pneumonia
- h influenza type B
Tb
Name 2 indications for routine steroids in Paeds infections
- Tb meningitis
- present deafness in H influenza B infection
Name 4 clinical features staph aureus
- Skin: impetigo, boils
- bones: osteomyelitis, septic arthritis
- resp: pneumonia, tracheitis
- cardio: endocarditis
Name 4 complications mumps
- Pancreatitis
- orchitis!
- meningitis
- sensorineural hearing loss
Simple vs complicated UTI?
Simple: lower tract only (cystitis, urethritis), few symptoms and signs
Complicated: upper tract, systemic symptoms and signs
Diagnosis UTI? (2)
- Urinalysis: bacterieria and/or pyuria
- culture: at least 50 000 CFu /ml, uropathogen
Indication for ultrasound in children with UTI?
All pre-pubertal children with documented culture proven UTI
(Not if previous normal ultrasound)
Treatment UTI (3)
Empiric amoxicillin - clavulanic acid
Adjust when cultures back
Complicated and older than 3 months: oral antibiotics 7-10 days, or Iv 2-4 days followed by oral 10 days
Hospitalize and iv if: younger than 3 months, urosepsis, children vomiting or can’t tolerate oral medication, immune compromised, no response to oral therapy
CSF results bacteria? (6)
Protein slightly elevated
Glucose very low
Chloride normal
Polymorphs abundant
Lymphocytes slightly increased
Red blood cells none
Most likely cause acute meningitis at 8 months
Strep pneumonia
CSf results of viral eg herpes encephalitis
Seizures, fever, irritable
Glucose normal
Neutrophils none
Red blood cells very high
Name 7 steps in diagnosing Tb
- History
- clinical exam
- Tst
- Igra (interferon gamma release assays)
- genexpert
- culture and sensitivity (gold standard)
- Cxr
Treatment uncomplicated Tb <8 years old?
- Rifampicin
- isoniazid (with pyridoxine to prevent peripheral neuropathy )
- Pyrazinamide
Treatment Tb meningitis?
- Rifampicin
- isoniazid
- pyrazinamide
- Ethionamide!
- prednisone
Name 9 clinical features of severe falciparum malaria according to WHO
At least 1
- Impaired consciousness
- Prostration (can’t sit/stand/ walk without assisstance)
- multiple convulsions: >2 in 24 hours
- acidotic breathing, respiratory distress
- Acute pulmonary oedema, ARDS
- Circulatory collapse or shock
- anuria
- jaundice
- abnormal bleeding
Name 7 lab and other features of severe falciparum malaria according to WHO
- Hypoglycaemia
- metabolic acidosis
- Severe normocytic anaemia (hb < 7 or Hct < 20%)
- hyperparasitaemic
- hyperlactataemia
- Renal impair (creatinine > 265)
- Pulmonary oedema - radiological
Treatment uncomplicated malaria caused by P falciparum/Malariae / Knowlesi?
- Antemether- lumefantrine (coartem)
If unavailable: oral quinine plus doxycycline/ clindamycin
Treatment uncomplicated malaria caused by P ovale/vivax or mixed infections falciparum plus ovale/vivax?
- Artemether lumefantrine
- followed by primaquine
Treatment severe malaria?
- iv artesunate (if not available, quinine)
- Once able to tolerate oral treatment, follow with artemether lumefantrine (coartem)
Name 7 contraindications lumbar puncture
- Decreased level of conciousness (glascow<13)
- signs/ raised intra-cranial pressure
- focal deficit eg unequal pupils
- too sick - haemodynamically unstable/ respiratory compromise
- septicaemia with petechia/ purpura
- Low platelets or DIC
- local skin infection
Normal CSF findings? (3)
- White cells: o neutrophils, 0-6 lymphocytes
- Protein: 0,15 - 0,45 g/l
- glucose: 3,6 - 5,6 mmoI/l
Tb meningitis CSF findings? (3)
- White cells: predominantly lymphocytes (other bacteria neutrophils)
- protein extremely high
- glucose very low
Cause false negative Mantoux test in child with TB? (10)
- Malnutrition
- HIV
- severe viral infections eg measles, chickenpox
- cancer
- immunosuppressive drugs eg steroids
- severe disseminated Tb
- Cutaneous energy
- recent Tb within 8-10 weeks; very old Tb many years
- very young < 6 months
- recent live virus vaccination eg measles, vzv
- incorrect method TST admin, incorrect interpretation
Cause false positive Mantoux test in child without TB? (3)
- Injected subcutaneous in right arm (area of previous BCG vaccination)
- infection with non-tb mycobacteria
- incorrect test admin, incorrect interpretation
Malaria prophylaxis child ? (2)
- chloroquine
- proguanil
Positive Mantoux test in HIV positive/ malnourished / severe illness
5 mm or more
Positive Mantoux test in healthy?
10 mm or more
Only measure induration, not erythema
Common cause pyrexia of unknown origin in developing countries?
Typhoid fever
Complication varicella?
Cerebellar ataxia
Define lymphocytic interstitial pneumonitis
Rare, infiltration alveolar interstitia and air spaces with small lymphocytes and plasma cells.
Most common cause pulmonary disease after pjp in HIV positive children or EBV.
Autoimmune or indirect viral etiology.
