Hexagonal crystals observed in a pediatric urine specimen are most strongly associated with which condition?

Hexagonal crystals observed in a pediatric urine specimen are most strongly associated with which condition?

• A. Upper urinary tract infection
• B. Maple syrup urine disease
• C. Cystinuria
• D. Glomerulonephritis

Answer: (C)

Hexagonal crystals in urine point to a problem with amino acid handling in the kidney, specifically cystinuria. In this condition, there is a defect in the proximal tubule’s reabsorption of dibasic amino acids, causing excess cystine to spill into the urine. Cystine is poorly soluble and forms the distinctive hexagonal crystals, which can lead to kidney stones in children. This crystal pattern is not typical of a urinary infection, maple syrup urine disease, or glomerulonephritis, which present with different signs and findings. Therefore, the hexagonal crystals most strongly indicate cystinuria.

Hexagonal crystals in urine point to a problem with amino acid handling in the kidney, specifically cystinuria. In this condition, there is a defect in the proximal tubule’s reabsorption of dibasic amino acids, causing excess cystine to spill into the urine. Cystine is poorly soluble and forms the distinctive hexagonal crystals, which can lead to kidney stones in children. This crystal pattern is not typical of a urinary infection, maple syrup urine disease, or glomerulonephritis, which present with different signs and findings. Therefore, the hexagonal crystals most strongly indicate cystinuria.