3. Paeds [Infection and Immunity] Flashcards
Which organism causes slapped cheek, and what is slapped cheek also referred to as?
Human Parvovirus B19
erythema infectiosum
Do children require school exclusion with slapped cheek?
No, once the rash has presented itself they are no longer infectious.
Describe the process of parvovirus B19 causing fetalis hydrops.
Vertical transmission from mother.
Viral suppression of fetal erythropoesis leads to heart failure secondary to severe anaemia.
The heart failure causes accumulation of fluid outside the intravascular space e.g. ascites, pleural & pericardial effusions.
Who could be affected by an aplastic crisis if infected with parvovirus B19
Chronic haemolytic anaemias e.g. sickle cell disease, thalassaemia
How would immunocompromised patients present with parvovirus B19 (lab wise)?
pancytopenic
Describe the classical chickenpox rash, including where it starts and where it spreads to.
Macular, papular then vesicular.
Starts on head and trunk, then progresses to peripheries.
Chickenpox is highly infectious. What route is it spread through, and when is the person carrying it infectious?
Respiratory route
Infected person is infectious 4 days before rash appears, and 5 days after it first appears.
What should immunocompromised patients and newborns with peripartum exposure to chickenpox be given?
Varicella zoster immunoglobulin (VZIg)
What is the most common complication of chickenpox, and what increases the risk of this?
Superimposed bacterial infection.
Small number could get group A strep soft tissue infection that may result in necrotizing fasciitis.
NSAIDs increase risk.
Give 3 rare complications of chickenpox.
Pneumonia
Disseminated haemorrhagic disease / DIC
Encephalitis
What information regarding school exclusion due to chickenpox should be given?
Patients are infectious 2 days before the rash starts, and until all the lesions are dry and have crusted over, usually 5 days after the rash starts.
What is shingles?
Reactivation of the dormant virus in the dorsal root ganglion (dermatomal distribution).
What is the antibiotic treatment for scarlet fever?
Penicillin V for 10 days
Azithromycin if allergic to penicillin
When can children who have suffered from scarlet fever return to school?
24 hours after starting antibiotics
Scarlet fever is usually a mild illness, but can have complications. Name 4.
Otitis media
Rheumatic fever
Acute glomerulonephritis
Invasive complications e.g. bacteraemia, meningitis, nec fasc
