Genitourinary Emergencies
Genitourinary complaints in children are frequently time-sensitive or presentationally subtle. The febrile infant is the classic trap: under 2–3 months, fever without a source requires a full sepsis evaluation including urinalysis, blood cultures, and empiric antibiotics. Collect the urine by catheter or suprapubic aspiration, never a bag specimen, for culture. Older children with pyelonephritis may present with vomiting and flank pain rather than typical urinary symptoms.
Acute scrotum
Testicular torsion is a surgical emergency with a window of roughly 6 hours. Suspect it with sudden onset pain, nausea and vomiting, an absent cremasteric reflex, and a high-riding transverse testis. Do not allow ultrasound to delay surgery when clinical suspicion is high, and know that manual detorsion is a temporizing option. Distinguish torsion from epididymitis (gradual onset, fever, preserved reflex) and from torsion of the appendix testis (focal "blue dot" sign).
Structural and systemic disease
Posterior urethral valves should be considered in a male infant with a poor urinary stream, palpable bladder, sepsis, or bilateral hydronephrosis. A newborn with a swollen, discolored scrotum may have a testicular or scrotal hydrocele, hernia, or trauma - transillumination helps but does not replace examination. Circumcision complications include bleeding, infection, and an obscured glans; hypospadias is a contraindication to routine circumcision at birth. Hemolytic uremic syndrome produces acute kidney injury with anemia and thrombocytopenia after a diarrheal illness. Hematuria warrants assessment for nephritis (hypertension, edema, cola-colored urine), stones, and trauma. Nephrotic syndrome presents with periorbital edema, weight gain, and massive proteinuria.
Rule of thumb: any male with acute scrotal pain and vomiting gets an immediate surgical referral - discuss the timing before ordering imaging.