Comprehensive Pediatrics Glossary

D

Definition: A state in which total body water is less than normal due to fluid loss, decreased intake, or a combination of both.
Pathophysiology:
- Children are more susceptible due to higher body water content, increased metabolic rate, and greater insensible losses.
- Classified as isotonic, hypertonic, or hypotonic depending on the relative sodium and water loss.
Clinical Features:
- Mild: Thirst, dry mucous membranes, decreased urine output.
- Moderate: Sunken eyes, reduced skin turgor, irritability, tachycardia.
- Severe: Lethargy, hypotension, weak pulses, shock.
Investigations: Serum electrolytes, blood urea nitrogen (BUN), creatinine, urine specific gravity.
Management:
- Oral Rehydration Solution (ORS) for mild to moderate cases.
- IV fluids (e.g., isotonic saline, Ringer’s lactate) for severe dehydration.
Relevance in Pediatrics: Commonly occurs in diarrhea, vomiting, or febrile illnesses.

Definition: Delay in achieving developmental milestones in one or more domains: motor, language, social, or cognitive.
Etiologies:
- Genetic: Down syndrome, Fragile X.
- Environmental: Malnutrition, neglect.
- Medical: Cerebral palsy, hypothyroidism.
Screening Tools: Denver Developmental Screening Test, Ages and Stages Questionnaire.
Management:
- Early intervention programs (speech therapy, occupational therapy).
- Treat underlying cause.
Prognosis: Varies with cause; early recognition improves outcomes.

Definition: A metabolic disorder characterized by chronic hyperglycemia due to insulin deficiency or resistance.
Types:
- Type 1: Autoimmune destruction of β-cells (most common in pediatrics).
- Type 2: Increasing in obese adolescents.
Clinical Features: Polyuria, polydipsia, weight loss, nocturia, recurrent infections.
Complications:
- Acute: Diabetic ketoacidosis (DKA).
- Chronic: Retinopathy, nephropathy, neuropathy.
Management:
- Insulin therapy (Type 1).
- Lifestyle modification ± oral hypoglycemics (Type 2).
Special Pediatric Considerations: Growth, puberty, school support, psychosocial aspects.

Definition: A life-threatening complication of diabetes mellitus due to insulin deficiency and increased counter-regulatory hormones.
Pathophysiology:
- Hyperglycemia → osmotic diuresis → dehydration.
- Lipolysis → ketone production → metabolic acidosis.
Clinical Features: Kussmaul breathing, fruity odor breath, abdominal pain, vomiting, altered sensorium.
Investigations:
- Blood glucose >11 mmol/L (>200 mg/dL).
- pH <7.3, HCO₃⁻ <15 mmol/L.
- Positive ketones in urine/serum.
Management:
- IV fluids (isotonic saline).
- IV insulin infusion (0.05–0.1 units/kg/hr).
- Potassium replacement once urine output is established.
Complication: Cerebral edema (unique pediatric risk).
Prognosis: Excellent with early recognition and treatment.

Definition: Passage of three or more loose or watery stools per day.
Types:
- Acute (≤14 days).
- Persistent (>14 days).
- Chronic (>30 days).
Etiologies:
- Infectious (rotavirus, E. coli, Shigella).
- Malabsorption (celiac disease, cystic fibrosis).
- Functional (toddler’s diarrhea).
Complications: Dehydration, malnutrition, electrolyte imbalance.
Management:
- ORS as first-line.
- Zinc supplementation (10–20 mg/day).
- Antibiotics only if dysentery or specific bacterial cause.
Prevention: Handwashing, breastfeeding, safe water, vaccination (rotavirus).

Definition: A chromosomal disorder caused by trisomy of chromosome 21.
Clinical Features:
- Dysmorphic facies: flat nasal bridge, epicanthal folds, upslanting palpebral fissures.
- Congenital heart disease (AV septal defect, VSD).
- Hypotonia, developmental delay.
- Increased risk of leukemia and hypothyroidism.
Diagnosis:
- Prenatal: Maternal serum screening, chorionic villus sampling, amniocentesis.
- Postnatal: Karyotyping.
Management:
- Multidisciplinary care (cardiology, endocrinology, speech therapy).
- Early intervention programs.
Prognosis: Life expectancy ~50–60 years with proper care.

Definition: X-linked recessive progressive myopathy due to mutation in the dystrophin gene.
Epidemiology: Most common muscular dystrophy in boys.
Clinical Features:
- Onset: 2–5 years.
- Gower’s sign (using hands to climb up legs when standing).
- Progressive proximal muscle weakness.
- Pseudohypertrophy of calves.
- Cardiomyopathy and respiratory complications in adolescence.
Investigations:
- Elevated serum creatine kinase.
- Genetic testing (dystrophin mutation).
- Muscle biopsy (absence of dystrophin).
Management:
- Corticosteroids (prednisolone, deflazacort).
- Physiotherapy, assisted ventilation.
- Cardiac and respiratory monitoring.
Prognosis: Loss of ambulation by age 12; life expectancy into late 20s–30s.

Definition: A specific learning disorder characterized by difficulty in reading, spelling, and writing despite normal intelligence and educational opportunity.
Clinical Features:
- Difficulty recognizing words, slow reading.
- Poor spelling and writing skills.
- Associated with ADHD or speech-language disorders.
Diagnosis: Educational and neuropsychological assessment.
Management:
- Specialized educational interventions.
- Speech and occupational therapy.
- Supportive environment.
Prognosis: Lifelong but manageable with early intervention.

Definition: Subjective sensation of difficulty in breathing, often described by parents as “trouble breathing.”
Etiologies:
- Respiratory: Asthma, bronchiolitis, pneumonia.
- Cardiac: Congenital heart disease, heart failure.
- Metabolic: Acidosis.
Clinical Assessment: Respiratory rate, oxygen saturation, chest retractions, nasal flaring, grunting.
Management: Depends on underlying cause (oxygen, bronchodilators, antibiotics, diuretics).
Relevance: Common pediatric emergency requiring rapid recognition and intervention.

Bookmark