O

• Obesity: Excess body fat adversely affecting health.

• Omphalocele: Congenital abdominal wall defect with herniation of abdominal organs covered by a membrane.

• Onychomycosis: Fungal infection of the nails.

• Ophthalmia Neonatorum: Conjunctivitis in the newborn caused by infection during birth.

• Osteogenesis Imperfecta: Genetic disorder causing brittle bones and frequent fractures.

• Osteomyelitis: Infection of bone tissue.

• Otosclerosis: Abnormal bone growth in the middle ear causing hearing loss.

• Ovarian Cysts: Fluid-filled sacs in the ovary, sometimes present in neonates and adolescents.

P

• Pallor: Unusual paleness of the skin or mucous membranes.

• Pancreatic Insufficiency: Inadequate production of pancreatic enzymes causing malabsorption.

• Pancytopenia: Reduction in red cells, white cells, and platelets.

• Pediatric Asthma: Chronic inflammatory airway disease with wheezing, cough, and dyspnea.

• Pertussis (Whooping Cough): Highly contagious bacterial infection causing paroxysmal cough.

• Phimosis: Inability to retract the foreskin of the penis.

• Phenylketonuria (PKU): Metabolic disorder causing accumulation of phenylalanine leading to neurotoxicity.

• Pneumonia: Infection of the lungs causing fever, cough, and difficulty breathing.

• Polycystic Kidney Disease (PKD): Genetic disorder causing multiple cysts in kidneys.

• Polydactyly: Presence of extra fingers or toes.

• Prematurity: Birth before 37 weeks of gestation.

• Primary Immunodeficiency Disorders: Genetic defects impairing immune system function.

• Prune Belly Syndrome: Congenital disorder with absent abdominal muscles, urinary tract anomalies, and cryptorchidism.

• Pulmonary Hypertension: Elevated pressure in the pulmonary arteries causing right heart strain.

Q

• Quadriplegia: Paralysis of all four limbs due to neurological injury.

• QT Prolongation: ECG abnormality increasing risk of ventricular arrhythmias.

• Quinsy (Peritonsillar Abscess): Deep infection behind the tonsil causing severe throat pain and fever.

R

• Rash: Visible skin eruption due to infection, allergy, or systemic disease.

• Respiratory Distress Syndrome (RDS): Neonatal lung immaturity causing difficulty breathing.

• Retinoblastoma: Malignant tumor of the retina, common in infants and young children.

• Retinopathy of Prematurity (ROP): Abnormal retinal blood vessel development in premature infants.

• Rickets: Vitamin D deficiency causing soft and weak bones.

• Rocky Mountain Spotted Fever: Tick-borne bacterial infection causing fever and rash.

• Rotavirus Infection: Viral gastroenteritis causing diarrhea and dehydration in infants.

S

• Sepsis: Life-threatening systemic response to infection.

• Sickle Cell Disease: Genetic disorder causing abnormal hemoglobin and chronic hemolysis.

• Slipped Capital Femoral Epiphysis (SCFE): Disorder of the hip in adolescents causing limping and pain.

• Spina Bifida: Neural tube defect causing incomplete closure of the spinal column.

• Strabismus: Misalignment of the eyes, commonly known as “crossed eyes.”

• Subgaleal Hemorrhage: Bleeding beneath the scalp, often post-birth trauma.

• Superior Vena Cava Syndrome: Obstruction of blood flow through the superior vena cava, rare in pediatrics.

• Syphilis (Congenital): Infection transmitted from mother to fetus causing multisystem disease.

T

• Tachypnea: Rapid breathing.

• Tay-Sachs Disease: Genetic neurodegenerative disorder causing developmental regression.

• Tonsillitis: Inflammation of the tonsils, often due to bacterial or viral infection.

• Transient Tachypnea of the Newborn (TTN): Temporary rapid breathing in neonates due to delayed lung fluid clearance.

• Trisomy 21 (Down Syndrome): Genetic disorder caused by an extra copy of chromosome 21.

• Turner Syndrome: Genetic disorder in females with complete or partial monosomy X, causing short stature and gonadal dysgenesis.

• Tuberculosis (Pediatric TB): Infection with Mycobacterium tuberculosis affecting children.

• Tumor Lysis Syndrome: Metabolic complication of cancer treatment causing electrolyte imbalance.

U

• Umbilical Hernia: Protrusion of abdominal contents through the umbilical ring.

• Urethral Stricture: Narrowing of the urethra causing urinary obstruction.

• Urinary Tract Infection (UTI): Infection affecting kidneys, ureters, bladder, or urethra.

• Urticaria: Hives; raised, itchy, red or skin-colored welts caused by allergic reactions.

• Uveitis: Inflammation of the uvea (eye), sometimes associated with systemic autoimmune disease.

V

• Varicella (Chickenpox): Highly contagious viral infection causing vesicular rash.

• Ventricular Septal Defect (VSD): Congenital hole in the heart’s ventricular septum.

• Ventriculoperitoneal Shunt: Surgical device to treat hydrocephalus.

• Vitamin K Deficiency Bleeding (VKDB): Bleeding tendency in newborns due to low vitamin K levels.

• Viral Exanthem: Rash caused by viral infection.

• Viral Hepatitis: Infection of the liver by hepatitis viruses A, B, or C.

W

• Wheezing: High-pitched whistling sound during breathing due to airway narrowing.

• Wilms Tumor: Malignant kidney tumor in children.

• Weight-for-Age: Standardized growth measure comparing a child’s weight to age-based norms.

• Wiskott-Aldrich Syndrome: X-linked immunodeficiency causing thrombocytopenia, eczema, and recurrent infections.

X

• X-linked Agammaglobulinemia: Genetic disorder leading to absence of B cells and recurrent infections.

• X-linked Recessive Disorders: Genetic disorders caused by mutations on the X chromosome, more severe in males.

• Xerophthalmia: Dry eyes due to vitamin A deficiency, potentially leading to blindness.

Y

• Yeast Infection (Candidiasis): Fungal infection affecting diaper area, oral cavity, or skin.

• Yaws: Chronic bacterial infection affecting skin, bones, and joints, mainly in tropical regions.

• Yolk Sac Tumor: Rare pediatric germ cell tumor, often occurring in infants and young children.

Z

• Zinc Deficiency: Low zinc levels causing growth retardation, skin lesions, and immune dysfunction.

• Zika Virus Infection: Viral infection causing fever, rash, and microcephaly in fetuses.

• Zollinger-Ellison Syndrome: Rare condition causing excessive gastric acid production, very rare in pediatric populations.

• Zygomycosis (Mucormycosis): Rare fungal infection affecting immunocompromised children.