Histomorphology of multiple myeloma on bone marrow biopsy.

In a retrospective study, 49 bone marrow biopsies (BMB) of patients with multiple myeloma (MM) were studied for its role in diagnosis and to determine histological parameters of prognostic significance. Sections were analyzed by 2 observers and classified according to: 1. Cytological grading according to differentiation of the neoplastic cells as plasmacytic, pleomorphic and plasmablastic. 2. Volume of infiltration: quantitating the percentage of myeloma cells in the biopsy. 3. Pattern of neoplastic infiltration. The overall marrow cellularity, presence of marrow fibrosis, micro-osteolesions and normal haematopoeisis were also studied. The bone marrow biopsy (BMB) was diagnostic for myeloma in five cases, where the aspirates were hypocellular: four had early myeloma and one had extensive marrow fibrosis. The pattern of infiltration was interstitial in 19 cases (39%), nodular in 19 cases (39%), and diffuse in 11 cases (22%). In majority of the cases (49%), the cell type was plasmacytic (24 cases), plasmablastic in 10 cases and pleomorphic in 15 cases. All cases of poorly differentiated cell type (plasmablastic) had a diffuse or nodular pattern of infiltration, whereas majority of the well-differentiated cell type had an interstitial pattern. The plasma cell burden in biopsy i.e the volume of infiltration was <10% in 8 cases, <50% in 19 cases and >50% in 22 cases and was used for histological staging of MM. Fibrosis was present in 30% of cases. Follow up was available in 11 cases, and cases with poorly differentiated myeloma, diffuse pattern of infiltration and dense fibrosis had survival less than one year. Cases of well differentiated myeloma, interstitial pattern of infiltration and plasma cell load less than 20% with absence of fibrosis had a more than 5-year survival. Different series have quoted that all these histological parameters provide valuable prognostic information, wherever other modalities like beta 2 microglobulin and IL-6 levels, etc are not available. The effects of therapy can also be monitored by sequential biopsies.

Role of the Parasight-F test in the diagnosis of complicated Plasmodium falciparum malarial infection

An evaluation was made of the diagnostic efficacy and utility of the Parasight-F test in diagnosing Plasmodium falciparum malaria, compared with conventional microscopy, particularly in severe and complicated cases. This study was designed as a prospective, case control hospital-based study. Febrile patients suspected to be suffering from malaria were selected randomly and were subjected to peripheral smear examinations (thick and thin) and Parasight-F tests till the required number of at least 30 cases of P. falciparum infection were identified, including at least 15 complicated cases. In addition 20 cases of P. vivax malarial infection as well as 20 healthy age and sex-matched individuals were taken as two control groups. The outcome measure was the number of cases with positive Parasight-F test results compared with conventional microscopy. Thirty-two patients with P. falciparum malaria were identified, with 15 severe and complicated cases. Peripheral smears were positive in 29 (91 percent) of these, while parasight-F test was positive in 31 out of 32 (97 percent) cases. Parasites were detected only by bone marrow examination in one case. Diagnostic sensitivity and specificity of peripheral smears for detecting falciparum infection were 90.6 percent and 100 percent respectively while that of the Parasight-F test were 96.8 percent and 100 percent, respectively (P>.05). The Parasight-F test has high sensitivity and specificity in diagnosing P. falciparum malarial infection, comparable to or even higher than microscopy exams, particularly in severe and complicated cases, with additional advantages of speed, simplicity and objectivity.