Paediatric Infections

Question 1

What is the normal number of resp infections per year in young children?

Answer 1

Up to 8/year (if in daycare, even more)

Question 2

What disorders may cause increased susceptibility to infection in children?

Answer 2

Atopic disease
Circulatory disorders eg sickle cell, diabetes
Obstructive eg asthma, urethral stenosis
Barrier failure eg eczema, fistula
Unusual micro factors eg resistant organisms
Foreign bodies eg shunt, artificial heart valve
Inadequate clearance eg hypotonia

Secondary
-prem
-hereditary diseases
-immunosuppressive agents eg steroids, radiation
-infectious diseases eg congenital rubella
-Surgery and trauma eg burns, splenectomy, anaesthesia

Question 3

What are the 10 warning signs of immunodeficiency?

Answer 3

Positive family history
>2 months on AB with little effect
>2 serious sinus infections in 1 year
4+ new ear infections in 1 year
>2 pneumonias in 1 year
Failure of infant to gain weight and grow normally
Recurrent deep skin or organ abscesses
Persistent thrush in mouth or fungal skin infection
Need for IV AB to clear infections
>2 deep seated infections including septicaemia

Question 4

Define primary immunodeficiency

Answer 4

A group of diverse illnesses that as a result of 1+ abnormalities of immune system, increase susceptibility to infection.

Question 5

How is the immune system categorised?

Answer 5

B cell (antibody)
T cell (cellular immunity)
Phagocytic (polymorphonuclear)
Complement

Question 6

What lab tests are used to evaluate possible immunodeficiency?

Answer 6

Complete blood count and diff
IgG, IgA, IgM, IgE
ESR
Tuberculin test
Chest + sinus X-ray
Urinanalysis
Exclude HIV and TB
Sweat test
Cultures

NB value ranges vary with ages

Question 7

Define fever of unknown origin

Answer 7

Temp more than 38,3 in whom no specific diagnosis after TWO outpatient visits or THREE days in hospital

Question 8

What can cause pyrexia of unknown origin?

Answer 8

Infections (HIV, TB, abscess, typhoid, malaria, UTI)
Collagen vascular disease
Malignancies
Miscellaneous
No cause found

Question 9

How do you treat fever of unknown origin?

Answer 9

① looks well and > 3 months temp <39
= observe, return if sx develop
②looks well and > 3months temp >39
= investigate as indicated, consider empiric antibiotics

③ looks well, < 3months, temp <39
= blood count and urine. If normal, return if sx develop
④ looks well <3months, temp > 39
= admit + investigate (urine + blood culture, FBC, CSF, CXR)

Question 10

Define petechia

Answer 10

Minute haemorrhages into the skin (1-3mm)

Question 11

Define purpura

Answer 11

Slightly larger groupers of adjoining petechiae

Question 12

Define ecchymosis

Answer 12

Large (>1-2cm) subcutaneous haematoma

Question 13

Classify bleeding disorders

Answer 13

① vessel wall
- infections
- drug reactions
- abnormal vessel wall

② platelets
- thrombocytopenia
- defective platelets

③ clotting factors

Or combinations

Question 14

Clinical features of measles

Answer 14

3 C’s
- conjunctivitis
- coryza
-cough
Fever
Maculopapular rash
Kopliks spots in buccal mucosa

Question 15

Complications of measles

Answer 15

Pneumonia (bacterial superinfection)
Immune suppression
LTB
Acute encephalitis
Encephalopathy
Diarrhoea
Otitis media
Corneal ulceration

Question 16

Clinical features of HH6?

Answer 16

Rosella infantum
Enlarged lymph nodes
Fever 3-7days
Undifferentiated febrile illness without rash
Febrile seizures in 15%

Question 17

What virus causes hand foot and mouth disease?

Answer 17

Coxackie A16
EV 71

Question 18

What causes scarlet fever?

Answer 18

Group A streptococcus

Question 19

Clinical features of herpes simplex in children

Answer 19

Gingivostomatitis
Fever, salivation and refusal to eat
Vesicles rupture shallow ulcers with red margin
4-9days
Local anaesthesia and tube feeds

Question 20

Complications of herpes simplex

Answer 20

Meningoencephalitis
Conjunctivitis
Recurrent disease
Disseminated disease

Question 21

Clinical signs of meningococcal meningitis

Answer 21

Early = URTI, fever, headache, vomiting, joint pain
Rash (haemorrhaging), purpurin lesions, petechiae
Circulatory collapse
Shock
Fever
Typical meningitis signs

Question 22

Complications of meningitis

Answer 22

Hydrocephalus
CN palsies
Cerebral oedema
Subdural empyema/effusion
Cerebral infarction
Hearing loss

Question 23

How do you diagnose meningococcal meningitis via lab?

Answer 23

Gold standard = culture (blood, CSF, petechiae)
Antigen detection (CSF, urine, serum)
Rapid diagnosis = gram stain
PCR

Leukopaenia
Thrombocytopenia
Inappropriate ADH secretion
Abnormal coagulation
Abnormal LFT

Question 24

Treatment of meningococcal meningitis

Answer 24

Prompt initiation of antibiotics = lifesaving
Empiric: ceftriaxone/penicillin/cefotaxime

Question 25

What are the two tick-bite fevers in Southern Africa?

Answer 25

Boutonneuse fever like (R. Conorii)
African TBF (R. Africae)

Question 26

What is the criteria for Kawasaki disease?

Answer 26

Fever lasting >5days
Bilateral conjunctival congestion
Changes of lips and oral cavity
Polymorphous exanthema
Changes in peripheral extremities
Acute non-purulent cervical lymphadenopathy

Question 27

How does one become infected with Malaria?

Answer 27

Female anopheles mosquito → blood meal → transfer plasmodium sorozities → incubation 10 - 21 days

Question 28

Signs and symptoms of Malaria

Answer 28

Fever
Chills
Headaches
Muscle/joint aches
Rigours,
Perspiration
Lethargy
Fatigue
Loss of appetite/poor feeding
Abdominal discomfort, nausea and vomiting
Cough
Splenomegaly

Question 29

How do you diagnose malaria?

Answer 29

RDT (rapid diagnostic test)
Blood smears

Question 30

What are the 8 steps of malaria management?

Answer 30

1) ABC
2) hypoglycaemia, cerebral malaria, anaemia, metabolic acidosis = important cx
3) agitation and resp distress
4) fluid boluses not recommended. Rather rehydration crystalsloids over 3-4hrs
5) secondary bacterial infections are common - give broad spectrum AB
6) renal failure and acute resp distress rare in young
7) meningitis = important differential (decreased LOC)
8) convulsions in children with malaria may be subtle and due to hypoglycaemia, cerebral malaria or pyrexia