Paediatric Bacterial and Parasitic Infections MCQs

Chlamydia is the most common cause of neonatal pneumonia associated with neonatal conjunctivitis. Chlamydial genital infection is reported in 5-30% of pregnant women, with a risk for vertical transmission at parturition to Newborn infants of approximately 50%. The infant may become infected at 1 or more sites, including the conjunctiva, nasopharynx, rectum, and vagina. Most commonly these infections manifest as inclusion conjunctivitis and Pneumonia. Rectal and vaginal infections are also seen but most of them are asymptomatic. TLC in these patients is normal to high & CXR often shows interstitial infiltrates. Drug of choice is usually IV Azithromycin Reference: Nelson textbook of Pediatrics, 20 th ed., pg. 1495

DiGeorge Syndrome DiGeorge syndrome is a congenital hypoplasia of organs derived from the third and fourth pharyngeal pouches. It results in hypoplasia or agenesis of the thymus and parathyroid glands, the auricle, and the external auditory canal; congenital cardiac anomalies; cleft palate; and short stature. It is associated with microdeletion of chromosome 22q11 . The main features are hypocalcemia, seizures, congenital heart disease, lymphocytopenia, and multiple minor anomalies. Hypocalcemia can manifest as apnea, jitteriness, crying episodes and tetany. Affected newborns may die from cardiac causes during the first month. Frequent infections due to a defect of cell-mediated immunity and failure to thrive may complicate the course of the surviving newborn. Reference: Nelson 20 th edition, pg-2650

HLA-DQ3+ predicts a more severe and fulminant course of congenital toxoplasma infection. According to Nelson, In monozygotic twins with congenital toxoplasmosis, the clinical pattern of involvement is most often similar, whereas in dizygotic twins the manifestations often differ. The major histocompatibility complex class II gene DQ3 appears to be common even among HIV-infected persons seropositive for T. gondii who develop toxoplasmic encephalitis, as well as in children with congenital toxoplasmosis who develop hydrocephalus. These findings suggest that the presence of HLA-DQ3 is a risk factor for severity of toxoplasmosis, in all patients including congenital toxoplasmosis. Reference: Nelson 21 st Edition, Chapter 316

CGD is an immune disorder where there is decreased NADPH dependent, free oxygen radicle production needed for killing catalase positive organisms. The diagnosis is most often made by performing flow cytometry using dihydrorhodamine 123 (DHR) to measure oxidant production through its increased fluorescence when oxidized by H2O2. Tags : Topic : IMMUNE DISORDERS Difficulty level : GOOD TO KNOW Reference : Nelson textbook of pediatrics, 1 st SA ed., pg. 1046

The child in the question has signs of CNS infection. Best method to confirm this is CSF culture. As the child already has a shunt in situ, it gives us an option to withdraw a sample of CSF via shunt and hence we can avoid an invasive LP procedure. Incorrect Options : Radionuclide scan and neuroimaging doesn't aid in the diagnosis of shunt infections Tags: Topic: CNS INFECTIONS Difficulty level: MUST KNOW PYQ: INICET NOV 2022 Reference: Nelson textbook of Pediatrics, 21 st ed., pg. 3079

Let us evaluate each option individually Option A is False. VUR is usually a cause of UTI rather than a result. Option B is False. E coli is the commonest organism isolated from UTIs. Option C is True. Risk factors for UTI include female gender, underlying VUR, constipation, neurological problems involving the bladder and bowel (spina bifida, operated sacro-coocygeal teratoma, etc. Bladder-bowel dysfunction (BBD) can cause recurrent UTI in Children. Option D is False. Long-term agents like Cotrimoxazole, Cephalexin, Cefadroxil and Nitrofurantoin are usually used as prophylactic agents. Amoxicillin is useful in treating UTI, but not recommended in prevention of UTI. Reference: OP Ghai 10 th Edition, Pages 507-511; Nelson textbook of pediatrics, 1 st SA ed., pg. 2559

It occurs in unimmunized mothers The contamination of umbilical stump during delivery is important cause. Usually presents in 3-12 days of life with feeding difficulties and excessive crying Treatment includes antibiotics- Penicillin G (Drug of choice), Metronidazole/erythromycin (alternative). Human tetanus immunoglobulin must be given in all cases. Tags : Topic : NEONATAL TETANUS Difficulty level : MUST KNOW Reference : Cloherty and starks manual of neonatal care, SA ed., pg. 731

Intrinsic factors get bound to the cobalamin in the duodenum and gets transported to the ileum. From the distal ileum, under alkaline conditions , the cobalamin is internalized in to the enterocytes and transported through the Transcobalamin. Overgrowth of bacteria in the small bowel can reduce the B12 absorption as they consume the vitamin or they disintegrate the cobalamin from the intrinsic factor. Tags : Topic : VITAMIN DEFICIENCY & TOXICITY Difficulty level : GOOD TO KNOW PYQ : FMGE JAN 2023; DEC 2021 Reference : Nelson textbook of pediatrics, 21 st ed., pg. 2520