Comprehensive Pediatrics Glossary

I

Definition: Group of inherited disorders characterized by dry, scaly skin due to abnormal keratinization.
Common Types:
- Ichthyosis vulgaris (autosomal dominant, mild, flexural sparing).
- X-linked ichthyosis (males, associated with steroid sulfatase deficiency).
- Lamellar ichthyosis (autosomal recessive, generalized thick scales at birth).
Clinical Features: Dry, rough, thickened skin; scaling may be generalized or localized.
Investigations: Primarily clinical; genetic testing if severe or syndromic.
Management: Regular emollients, keratolytic agents, topical retinoids in severe cases.

Definition: Acquired autoimmune disorder causing isolated thrombocytopenia in children.
Clinical Features: Petechiae, purpura, mucosal bleeding; usually otherwise well child.
Etiology: Often follows viral infection; autoantibodies target platelet antigens.
Investigations: CBC (isolated low platelets), peripheral smear, bone marrow if atypical.
Management:
- Most cases self-limiting: observation.
- Severe bleeding: IV immunoglobulin, corticosteroids.
Prognosis: Excellent; chronic ITP rare in children.

Definition: Superficial bacterial skin infection caused by Staphylococcus aureus or Streptococcus pyogenes.
Clinical Features:
- Non-bullous: Honey-colored crusts on face and extremities.
- Bullous: Fluid-filled blisters that rupture easily.
Investigations: Clinical diagnosis; culture if atypical or resistant.
Management: Topical mupirocin for localized lesions; oral antibiotics (e.g., cephalexin) for extensive disease.
Complications: Post-streptococcal glomerulonephritis.

Definition: Group of genetic disorders causing enzyme deficiencies leading to accumulation or deficiency of metabolites.
Examples:
- Phenylketonuria (PKU): Phenylalanine hydroxylase deficiency → intellectual disability if untreated.
- Maple Syrup Urine Disease: Branched-chain ketoacid dehydrogenase deficiency → neurologic crises.
- Urea cycle defects: Hyperammonemia, poor feeding, lethargy.
Investigations: Newborn screening, plasma amino acids, urine organic acids, enzyme assays.
Management: Dietary restrictions, supplements, emergency metabolic management.

Definition: Acute lymphoproliferative disease caused by Epstein-Barr virus (EBV).
Clinical Features: Fever, pharyngitis, cervical lymphadenopathy, hepatosplenomegaly, fatigue.
Investigations:
- Monospot test (heterophile antibodies), EBV serology.
- CBC: atypical lymphocytosis.
Management: Supportive care, avoid contact sports due to splenomegaly.
Complications: Hemolytic anemia, thrombocytopenia, airway obstruction (rare).

Definition: Infection of the endocardial surface of the heart, commonly affecting valves.
Etiology: Streptococcus viridans, Staphylococcus aureus, congenital heart disease predisposes.
Clinical Features: Fever, new murmur, malaise, splinter hemorrhages, Janeway lesions (rare in children).
Investigations: Blood cultures, echocardiography (vegetations), CBC, ESR.
Management: IV antibiotics (usually 4–6 weeks), surgical intervention for refractory cases.

Definition: Recurrent, prolonged, and intense crying in otherwise healthy infants <3 months old.
Etiology: Multifactorial: gastrointestinal immaturity, gas, parental anxiety, diet.
Clinical Features: Episodes >3 hours/day, >3 days/week, >3 weeks.
Management:
- Reassurance, soothing techniques, dietary adjustments (maternal elimination diet if breastfeeding).
- Pharmacologic therapy rarely needed.
Prognosis: Self-limiting, usually resolves by 3–4 months of age.

Definition: Anemia due to insufficient iron for hemoglobin synthesis, most common pediatric nutritional deficiency.
Etiology: Inadequate dietary intake, chronic blood loss, prematurity, cow’s milk overuse.
Clinical Features: Pallor, fatigue, irritability, pica, koilonychia in older children.
Investigations: CBC (microcytic hypochromic), serum ferritin, iron, TIBC.
Management: Oral iron supplementation, dietary counseling.
Complications: Developmental delay, growth retardation if prolonged.

Definition: Telescoping of one segment of intestine into another, causing bowel obstruction.
Epidemiology: Most common between 6–24 months.
Clinical Features: Sudden colicky abdominal pain, vomiting, “currant jelly” stools, palpable sausage-shaped mass.
Investigations: Ultrasound (target sign), contrast enema (diagnostic and therapeutic).
Management: Non-surgical reduction (air or contrast enema); surgery if perforation or failed reduction.

Definition: Congenital abnormal rotation of midgut around superior mesenteric artery.
Clinical Features: Bilious vomiting, abdominal pain, failure to thrive, intermittent obstruction.
Investigations: Upper GI contrast study (corkscrew appearance for volvulus).
Management: Surgical correction (Ladd procedure), emergency if volvulus present.

Definition: Excessive iron accumulation leading to organ dysfunction.
Etiology: Rare hereditary forms, chronic transfusions (thalassemia, sickle cell).
Clinical Features: Hepatomegaly, cardiomyopathy, endocrinopathy, growth retardation.
Investigations: Serum ferritin, transferrin saturation, genetic testing.
Management: Phlebotomy or chelation therapy (deferoxamine, deferasirox).

Definition: Developmental anomalies affecting kidneys, ureters, bladder.
Examples: Renal agenesis, duplex kidney, ureteropelvic junction obstruction, posterior urethral valves.
Clinical Features: Often asymptomatic; recurrent UTIs, failure to thrive, hypertension.
Investigations: Ultrasound, VCUG, renal function tests.
Management: Observation, prophylactic antibiotics, surgical intervention if obstruction or recurrent infection.

Definition: Rare hereditary anemia resistant to oral iron due to TMPRSS6 mutation affecting hepcidin regulation.
Clinical Features: Chronic microcytic anemia unresponsive to oral iron; fatigue, pallor.
Investigations: Low MCV, low ferritin, low transferrin saturation, genetic testing.
Management: IV iron supplementation; avoid ineffective oral iron therapy.

Bookmark