Diagnosis of cystinosis from a bone marrow aspirate

Abstract

A 4-year-old boy presented with pallor, visual problems and recurrent multiple bilateral renal stones that had been unresponsive to (non-specific) medical treatment. He had seen a number of physicians over a period of two years without a diagnosis being made. He was found to have pancytopenia, the blood count showing: white cell count 3.1 3 10 9 /l, hemoglobin concentration 86 g/l, and platelet count 102 3 10 9 /l. A bone marrow aspirate was performed to investigate the pancytopenia and revealed numerous clear cystine crystals, apparently free and within macrophages (images). This rare lysosomal storage disease is readily diagnosed from a bone marrow aspirate because of the presence of distinctive non-staining crystals. The crystals have straight edges and, when seen end on, are hexagonal (lower image).

Short‐cut diagnostic tool in cystinosis: Bone marrow aspiration

“…reported on a 4‐year‐old boy with pallor, visual problems and recurrent multiple bilateral renal stones and pancytopenia. Bone marrow aspiration showed numerous clear cystine crystals, apparently free and within macrophages, and cystinosis diagnosis was made . In a 1''‐year‐old boy presenting with growth failure, polyuria and polydipsia, bone marrow aspiration indicated increased numbers of macrophages containing polygonal crystals .…”

“…Here we present the cases of 10 patients with NC who were diagnosed on cystine deposition in bone marrow aspiration. There are only 12 reported cases of bone marrow involvement in NC . NC diagnosis is made on the observation of corneal cystine crystals and/or measurement of the cystine content of leukocytes, but typical crystals in the bone marrow are diagnostic .…”

“…There are only 12 reported cases of bone marrow involvement in NC. [11][12][13][14][15][16][17][18][19][20][21][22] NC diagnosis is made on the observation of corneal cystine crystals and/or measurement of the cystine content of leukocytes, 2 but typical crystals in the bone marrow are diagnostic. 22 The diagnosis can be confirmed on genetic analysis, but leukocyte cystine measurement and, CTNS analysis are not widely available.…”

“…Bone marrow aspiration showed numerous clear cystine crystals, apparently free and within macrophages, and cystinosis diagnosis was made. 16 In a 1"-year-old boy presenting with growth failure, polyuria and polydipsia, bone marrow aspiration indicated increased numbers of macrophages containing polygonal crystals. 22 Cystinosis diagnosis was made on these findings and on the observation of corneal cystine crystals.…”

Pancytopenia in a patient with cystinosis secondary to myelosuppression from cystine crystal deposition: a case report

“…These patients most often develop end-organ dysfunction of the kidneys, eyes, and endocrine system with a mean life expectancy of 28.5 years [ 1 , 3 ]. In rare cases patients will also develop complications of pancytopenia secondary to bone marrow suppression from cystine crystal deposition [ 4 – 9 ]. Here we report a rare case of pancytopenia in a patient with cystinosis secondary to myelosuppression from cystine crystal deposition.…”