Red cell fragmentation (schistocytosis) after bone marrow transplantation

Abstract

Summary:Red cell fragmentation is often the earliest sign of thrombotic microangiopathy. Days +14, +28 and +42 blood films from 58 allograft and 32 autograft recipients were reviewed blind to determine the incidence and severity of schistocytosis (the number of fragmented red cells per 1000 red cells expressed as a percentage). Schistocytosis was graded as mild (Ͻ1%), moderate (1-1.9%) or severe (у2%). Schistocytes were seen in 99% of day 14 films (0.1-3.0%, median 0.4%), 97% of day 28 films (0.1-3.2%, median 0.4%), and 98% of day 42 films (0.1-4.3%, median 0.5%). Nine patients (10%) had severe fragmentation and 20 patients (22%) had moderate fragmentation at some time or the other. The difference in the extent of fragmentation between the days was not significant. Allogeneic BMT was associated with more extensive fragmentation than autologous transplantation on day 28 (P = 0.008) and day 42 (P = 0.02). Age, conditioning regimen and diagnosis had no influence. None of the patients followed-up for 6 months after transplant developed full-blown thrombotic microangiopathy. The occasional patient showing mild clinical and laboratory features of hemolysis responded well to adjustment of fluid balance and cyclosporine dose where applicable. Our data indicate that mild red cell fragmentation is a common morphologic finding after transplantation with no clinical significance in the absence of other clinical and laboratory findings suggestive of thrombotic microangiopathy, although patients with moderate or severe fragmentation should be monitored closely.

Intestinal thrombotic microangiopathy after allogeneic bone marrow transplantation: a clinical imitator of acute enteric graft-versus-host disease

“…2 A single observer counted 500 red blood cells on blinded smears and calculated the percentage of fragmented erythrocytes retrospectively. A fragmented erythrocyte was defined as a schistocyte (crescent, helmet or triangle) 2,20 and the LDH/platelet ratio as described previously. 2 …”

Diagnostic criteria for hematopoietic stem cell transplant-associated microangiopathy: results of a consensus process by an International Working Group

“…1,[13][14][15] The reported proportions of patients developing a clinically significant microangiopathy syndrome have varied greatly. Recently George and co-workers 12 presented a review of published reports on microangiopathy following allogeneic stem cell transplantation.…”

Automated measurement of schistocytes after bone marrow transplantation

“…Thus, frequent (twice a week) schistocyte monitoring is mandatory to detect the laboratory picture of TMA during the follow-up of BMT. 2 The identification of schistocytes is usually carried out under the microscope from a stained PB smear. Since the shapes to which they correspond are frequently questionable, a consensus has been proposed by the Groupe Franc¸ais d'He´matologie Cellulaire (GFHC, French Group of Cellular Hematology).…”