Value of testis biopsy in the diagnosis of systemic amyloidosis.

Objectives: To evaluate testis biopsy as a diagnostic tool in systemic amyloidosis, to assess how amyloidosis affects testicular tissue, and to examine the relationship between testicular amyloidosis and infertility.

Methods: Testicular biopsies from 72 patients with confirmed systemic amyloidosis were examined for amyloid deposition after Congo red and crystal violet staining. A rectal biopsy was also done in each case, and the results were compared with the testicular biopsy findings.

Results: Testicular amyloid deposition was detected in 62 (86.1%) of 72 patients. Fifty-one (85%) of 60 patients with secondary amyloidosis, 11 (91.7%) of 12 patients with primary amyloidosis, and 28 (87.5%) of 32 patients with familial Mediterranean fever showed amyloid deposition in the testis. Rectal biopsies were positive in 40 cases (55.6%). Only 4 of the 62 patients with testicular amyloid showed normal spermatogenesis. The remaining 58 exhibited abnormal spermatogenesis, and 77.7% of patients had seconder infertility. Of 62 patients with positive testis biopsies, 30 had serum creatinine levels less than 1.5 mg/dL, and 29 patients with testicular amyloid manifested nephrotic syndrome.

Conclusions: The testis biopsy is a valuable and more sensitive method than rectal biopsy for diagnosing systemic amyloidosis. The results also showed that testicular amyloidosis causes infertility at a higher rate than expected.