Side scatter versus CD45 flow cytometric plot can distinguish acute leukaemia subtypes.

Background & objectives: Flow cytometry is an important tool to diagnose acute leukaemia. Attempts are being made to find the minimal number of antibodies for correctly diagnosing acute leukaemia subtypes. The present study was designed to evaluate the analysis of side scatter (SSC) versus CD45 flow dot plot to distinguish acute myeloid leukaemia (AML) from acute lymphoblastic leukaemia (ALL), with minimal immunological markers. Methods: One hundred consecutive cases of acute leukaemia were evaluated for blast cluster on SSC versus CD45 plots. The parameters studied included visual shape, CD45 and side scatter expression, continuity with residual granulocytes/lymphocytes/monocytes and ratio of maximum width to maximum height (w/h). The final diagnosis of ALL and AML and their subtypes was made by morphology, cytochemistry and immunophenotyping. Two sample Wilcoxon rank-sum (Mann Whitney) test and Kruskal-Wallis equality-of-populations rank tests were applied to elucidate the significance of the above ratios of blast cluster for diagnosis of ALL, AML and their subtypes. Receiver operating characteristic (ROC) curves were generated and the optimal cut-offs of the w/h ratio to distinguish between ALL and AML determined. Results: Of the 100 cases, 57 of ALL and 43 cases of AML were diagnosed. The median w/h ratio of blast population was 3.8 for ALL and 1 for AML (P<0.001). ROC had area under curve of 0.9772.The optimal cut-off of the w/h ratio for distinction of ALL from AML was found to be 1.6. Interpretation & conclusions: Our findings suggest that if w/h ratio on SSC versus CD45 plot is less than 1.6, AML may be considered, and if it is more than 1.6, ALL may be diagnosed. Using morphometric analysis of the blast cluster on SSC versus CD45, it was possible to distinguish between ALL and AML, and their subtypes.

Cocaine dependence: A case series from India.

Background. Cocaine use and dependence is a wellknown phenomenon in the West but has not been reported in the medical literature from India, despite recent media reports of its use by drug abusers and seizure by authorities. Methods. We report 5 patients with cocaine dependence who came for treatment to the Department of Psychiatry, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh. Results. All the patients were young adult men (age range 20–27 years). They were either unemployed or in mediumlevel occupation. All used cocaine by ‘snorting’ (inhaling cocaine hydrochloride salt in a powder form through the nose so that cocaine gets rapidly absorbed into the bloodstream through the nasal mucosal epithelial capillary vasculature). None reported smoking or inhaling the vapour of heated freebase cocaine (‘crack’). All reported intense and specific craving for cocaine (and met criteria for dependence syndrome as per ICD-10), though 3 patients were also dependent on opioid preparations (heroin, dextropropoxyphene or codeinecontaining cough syrups). We started them on clonidine for opioid detoxification followed by naltrexone. Since there is no approved medication for cocaine withdrawal or relapse prevention, our focus was on relapse prevention counselling using cognitive behavioural principles. The outcome was variable. Conclusion. Cocaine dependence is present among the population in India. Patients are not necessarily from the affluent class. This case series of cocaine dependence, the first from India, intends to be both a curtain raiser and an eyeopener.

Assessment of three simple techniques for the screening of circulating immune complexes: Correlation with a parameter of complement consumption.

The sera of 36 normal controls, 45 patients with various diseases and 11 pregnant women were screened for circulating immune complexes using three relatively simple and inexpensive techniques. These included inhibition of agglutination of IgG coated latex particles with a serum having rheumatoid factor activity, polyethylene glycol precipitation and anti-complementary activity test. The circulating immune complexes were detected in a significantly higher proportion of patients as compared to normal controls. In the patients, the presence of circulating immune complexes did not always correlate with clinically detectable immunoinflammatory tissue damage indicating that pathogenic as well as nonpathogenic immune complexes were being detected by the above mentioned techniques. The alpha-1- antitrypsin/C3 ratio, however, correlated well with clinically apparent immunoinflammation.