Erroneous values for the total white cell count and ESR in patients with cryoglobulinaemia.

Abstract

SYNOPSIs Temperature dependent fluctuations in the erythrocyte sedimentation rate were noted during the assessment of one patient with symptomatic cryoglobulinaemia. Two patients with this condition were found to have erroneously high leucocyte counts when estimated by the Model S Coulter Counter. The artefact was directly related to the degree of exposure to cold before the estimation was performed and appeared to be due to the formation of microaggregates of cryoglobulin and fibrinogen.Cryoglobulins are cold-precipitable immunoglobulins which redissolve at warm temperatures. These serum proteins have been described in a variety of clinical conditions in man (Ritzman and Levin, 1961), but particularly in individuals with various infections, autoimmune and neoplastic disorders (Mackay et al, 1956;Meltzer et al, 1966;Barnett et al, 1970).In assessing one patient with symptomatic cryoglobulinaemia, fluctuations in the erythrocyte sedimentation rate were noted. In addition, the same patient demonstrated erroneously high leucocyte counts when the Model S Coulter Counter was used but normal values when counting was performed by hand. The variations in ESR and WBC counts were found to be temperature dependent and thus susceptible to environmental conditions. A further patient with symptomatic cryoglobulinaemia also showed similar changes in leucocyte counts.

Spurious counts and spurious results on haematology analysers: a review. Part II: white blood cells, red blood cells, haemoglobin, red cell indices and reticulocytes

“…The presence of cryoglobulin was first reported as causing erroneous WBC counts (Emori, Bluestone & Goldsberg, 1973; Taft et al. , 1973; Haeney, 1976; Gulliani, Hyun & Gabaldon, 1977), but it also leads in many instances to spuriously elevated PLT counts, and at times to altered RBC counts or Hb measurements (cf., see Fohlen‐Walter et al. , 2002).…”

Detection of cryoglobulins by Coulter Counter model S-Plus IV/D

“…The presence of cryoglobulin may affect other haematological laboratory tests, particularly the erythrocyte sedimentation rate (Haeney 1976), leucocyte count (Emori, Bluestone & Goldberg 1973;Taft et at. 1973;Shah et at.…”

Pseudospontaneous Platelet Aggregation and Spuriously Elevated Blood Cell Counts in Cryoglobulinemia

“…Pseudoleukocytosis due to cryoglobulinemia is a welldescribed, but still unfamiliar event (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11). There are few records about this phenomenon in the hematologic literature (2,3,11), and it is generally not mentioned in the hematology textbooks.…”

“…In automated blood cell counting systems, cryoglobulinemia has been reported to cause spuriously elevated platelet and/or white blood cell (WBC) counts due to temperature-dependent protein precipitates that are falsely interpreted as blood cells at room temperature (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11). Upon heating to 37°C, these blood counts decrease to normal levels as cryoproteins dissolve.…”