Brown-Red Urinary Sediment as a Rare Macroscopic Finding in a 30-Month-Old Girl with Overt Hypothyroidism: A Case Report

Abstract

Hypothyroidism in children is a prevalent endocrine disorder characterized by insufficient production of thyroid hormones, significantly impacting physical growth, neurodevelopment, and metabolism. This case report presents a child exhibiting atypical manifestations. A 30-month-old (approximately 2.5 years) girl presented with a chief complaint of brown-red particles in her urine. Initial investigations, including repeated urinalyses and abdominal-pelvic ultrasonography, yielded normal results. Importantly, repeated microscopic examinations of the urine samples revealed no crystals or abnormal cellular elements, confirming that the visible particles were purely macroscopic. Despite treatment for a suspected mild urinary tract infection, the symptom persisted. Growth parameters were within normal limits. Following consultation, thyroid function tests revealed elevated thyroid-stimulating hormone (TSH: 9.09 μIU/mL) and low total thyroxine (T4: 6.4 μg/dL), with normal anti-thyroid peroxidase antibodies, confirming a diagnosis of overt hypothyroidism. Upon diagnosis, levothyroxine therapy was initiated, leading to rapid symptom improvement and complete resolution of the urinary particles within days. This case underscores the importance of considering overt hypothyroidism in children with nonspecific urinary symptoms and highlights the value of meticulous clinical follow-up.