Background: Urinary cytology is an uncommon investigative tool for pediatric tumors.
Case: A 16-month-old infant presented for investigation ofhematuria and blood clots into diapers. Urinary cytology showed a population of small, round, blue cells with little cytoplasm and high nuclear/cytoplasmic ratios. The cells were positive for desmin and negative for cytokeratin. A cytologic diagnosis of embryonal rhabdomyosarcoma was offered and subsequently confirmed by histopathology.
Conclusion: Embryonal rhabdomyosarcomas are not uncommon in the pediatric population. Urinary cytology may be useful for rapid diagnosis and early management of such cases.