1. Fig-2: Sample in Red topped clot activator tubes
Inseparable serum: An indicator of Hematological Malignancy?
Sudhanshu Shekhar, Tapasyapreeti Mukhopadhyay, Parul Arora, Samanyoya Gochhait, Raghavendra Lingaih, Sudip K Datta Department of Laboratory Medicine, All India Institute of Medical Sciences, New Delhi
Introduction
Hyperviscosity syndrome (HVS) refers to the clinical sequelae of increased blood viscosity.
Increased serum viscosity is usually due to increased circulating serum immunoglobulins that could result in inseparable serum.
We present two cases of HVS due to hypergammopathy, with a history of repeated sample rejection due to inseparable serum; thus, failing to obtain biochemical profile.
Apart from performing routine chemistry profile, serum was also essential for carrying out electrophoresis, thus posing an analytical challenge. Relevant steps were taken to combat the same.
Gel
Serum
Fig-1: Sample in Yellow topped gel serum separator tubes with clot activator
Fig-2: Sample in Red topped clot activator tubes
Results
First case was found to be a case of 46 year old male with Multiple myeloma. Total protein was 8.6g/dL with A/G ratio 1:3.
The second case was of a 55 year old male with Waldenstrom macroglobulinemia. Total protein was 8.3g/dL and A/G ratio 1:3.
On electrophoresis M band was seen in both, 55.3% or 4.8g/dL in case one and 54.5% or 4.5g/dL in case two respectively.
Material and Methods
Discussion
A few case reports suggest that multiple myeloma and related disorders are associated with improper gel barrier formation [2,3,4].
It is suggested that myeloma paraprotein inhibits all three stages of fibrin formation: the proteolytic action of thrombin on fibrinogen, the aggregation of fibrin monomers, and the stabilization of fibrin by cross-linkages in the γ and α chains [5].
Tubes in the clinical laboratory must be visually screened for any improper separation post-centrifugation.
Cryoglobulins are serum immunoglobulins that precipitate at temperatures below 370C and re-dissolve on warming. Studies suggest that sample temperature should be maintained at 370C in those cases until the serum is separated [1].
Conclusions
Inseparable serum in gel tubes could be a pointer towards hyperviscosity syndrome due to hypergammopathy as found in these cases.
This may be due to highly viscous serum forming a layer below the separator gel which can be overcome by using plain vacutainer tubes and incubating at 370 C before centrifugation.
References
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