M. Sivakumaran

The presence of free infectious cytomegalovirus (CMV) in the plasma of donated CMV-seropositive blood and platelets.

An in vitro study was carried out to determine the presence of free infectious CMV in the supernatant of donated units of blood and platelets which were known to be CMV seropositive. One sample was taken from each of 10 units of CMV‐seropositive platelet donations which were 4 days old. Ten units of seropositive blood were sampled at intervals over their storage lifespan. Each sample was divided into two and thrombin was added to one of them. The samples were all prepared by centrifugation. The resulting supernatant from the clotted samples was used in in vitro culture studies using the MRC‐5 cell line to ascertain the infectivity of the samples. The anticoagulated supernatants were subjected to PCR analysis to detect the presence of free genomic CMV DNA. All of the units of blood and platelets tested positive for the presence of genomic CMV DNA by PCR. Seven out of the 10 units of blood were culture positive from samples taken 3–4 weeks into their shelf‐life. None of the platelet samples was culture positive. The cultures of supernatants taken from seropositive blood were negative when the units were fresh, but further into their storage life, the cultures became positive, indicating that infectious material was released into the supernatant during storage, presumably due to the breakdown of intact white cells.

Paroxysmal cold haemoglobinuria caused by non-Hodgkin's lymphoma

Paroxysmal cold haemoglobinuria is an autoimmune haemolytic anaemia characterized by a biphasic polyclonal IgG autoantibody, the Donath‐Landsteiner (D‐L) antibody. Although classically described in association with chronic syphilis, it is most commonly seen after acute viral infections in children. We describe a case of high‐grade B‐cell non‐Hodgkins lymphoma which presented with paroxysmal cold haemoglobinuria. The lymphoma responded promptly to combination chemotherapy whilst, at the same time, the haemolytic process rapidly resolved. Subsequent investigations showed that the D‐L antibody originated from the lymphoma cells.

Aberrant CD8 antigen expression in a patient with B chronic lyrnphocytic leukaemia showing unusual disease progression

Summary. Co‐expression of T cell antigens in B‐CLL has been well recognized. The commonest T cell antigen known to be expressed in B‐CLL is CD 5, and recent reports suggest that CU 5 expression is associated with good prognosis. Expression of CD8 antigen, however, is much less common with uncertain prognostic significance. We report a case of B‐CLL with aberrant CD8 expression, who had unusual disease progression with a fatal outcome.

A new method to study the efficiency of third generation blood filters.

Summary. In order to study the efficiency of third generation blood filters we have devised a new method using 3 μm pore size polycarbonate filter membranes and a filtration chamber to trap leucocytes passing through the blood filter. The method has enabled us to make two important observations: (1) The filters function very efficiently at the start but the efficiency diminishes progressively with time. (2) When the blood flow through the filter is retarded, due to defective priming and/or filter malfunction, the filters fail even at the outset of the transfusion.

Acute lymphoblastic transformation of essential thrombocythaemia.

Essential thrombocythaemia is a myelopro‐Iterative disorder which may transform to acute myeloid leukaemia, especially following therapy with alkylating agents or radioactive phosphorus. We describe the rare occurrence of acute lymphoblastic leukaemia transformation in a patient with known essential thrombocythaemia.

TREATMENT OF ALLOIMMUNIZED. THROMBOCYTOPENIC PATIENT WITH ACID-TREATED RANDOM DONOR PLATELETS

0.34 x 10y/l (range0.001-1.26); 34(33%)hadaCD4count < 0.2 x 1 Oy/l and 3 1 (30%) had CD4IV disease. There is no significant difference between the two groups. We concluded that although 18% of HIV infected haemophiliacs do not have antibodies against C-100 (NS4 derived peptides) this is not related to the progression of HIV disease. However, there was 96% incidence of HCV infection as assayed using other epitopes and it would seem likely that any recipient of unheated clotting factor concentrate will have been infected with HCV. The reaction patterns for the three heterosexual partners infected with HIV are shown in Table I. The only patient showing HCV infection was the previous drug user. Amongst 3 1 partners of anti-HIV haemophiliacs we have found only one infected with HCV. Although sexual transmission may occur it is probably uncommon.

REMOVAL OF CYTOMEGALOVIRUS (CMV) INFECTED LEUCOCYTES FROM CMV SEROPOSITIVE BLOOD UNITS BY BEDSIDE BLOOD FILTRATION

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