Black-Colored Ligamentum Flavum Due to Alkaptonuria

Abstract

Alkaptonuria is a rare metabolic disease caused by deficiency of homogentisic acid oxidase and characterized by bluish-black discoloration of cartilages and skin (ochronosis). Defective production of this enzyme results in the accumulation of homogentisic acid (HGA), a tyrosine degradation product, in the bloodstream. Accumulation of HGA and its metabolites in tissues causes ochronosis. The word ochronosis refers to the dark bluish-black discoloration of connective tissues including the sclera, cornea, auricular cartilage, heart valves, articular cartilage, tendons, and ligaments. Neurogenic claudication resulting from focal hypertrophy of the ligamentum flavum in the lumbar spine due to ochronotic deposits has only been previously reported once in the literature. In this article, we present a 71-year-old male patient with alkaptonuria-associated degenerative L3–L4–L5 stenosis, diagnosed after lumbar decompressive laminectomy.

Keywords

black colored - ligamentum flavum - alkaptonuria

• References

• 1 Kalevski SK, Haritonov DG, Peev NA. Alcaptonuria with lumbar disc prolapse: case study and review of the literature. Spine J 2007; 7 (04) 495-498
• 2 Reddy R, Vijayasaradhi M, Biswal D. Focal ligamentum flavum hypertrophy with ochronotic deposits: an unusual cause for neurogenic claudication in alkaptonuria. Asian Spine J 2012; 6 (02) 148-151
• 3 Osun A, Korkmaz M, Temiz P, Samancioglu A, Atay B. Black colored intervertebral disc; ochronosis: a case report. Turk J Phys Med Rehab 2017; 63 (01) 78-81
• 4 Aydeniz A, Karslıgil T, Gursoy S. Associations between low back pain, disability, functional status, and serum interleukin-1 β level. Turk J Med Sci 2009; 39 (04) 613-617
• 5 Robbani I, Kak S, Mohan V, Sharma R. Ochronosis or alkaptonuric arthropathy. JK Science 2000; 2: 102-104
• 6 Panjabi MM. The stabilizing system of the spine. Part I. Function, dysfunction, adaptation, and enhancement. J Spinal Disord 1992; 5 (04) 383-389 ; discussion 397
• 7 Pratibha K, Seenappa T, Ranganath K. Alkaptonuric ochronosis: report of a case and brief review. Indian J Clin Biochem 2007; 22 (02) 158-161
• 8 Collins E, Hand R. Alkaptonuric ochronosis: a case report. AANA J 2005; 73 (01) 41-46