ABSTRACT
To document overall performance and improvement, if any, gained through participation in an International External Quality Assessment Scheme [IEQAS]. Descriptive study. The Haematology Department, Public Health Laboratories Division, National Institute of Health, Islamabad, Pakistan, from January 1996 to December 2006. Overall performance of blood parameters and parasite identification were analysed. Individual values were assessed against consensus value [mean +/- SD] and deviation index [DI] from the mean, whereas coefficients of variation [CV] were calculated for years 1996 to 2006. The results are expressed as percentage of accurate versus inaccurate results, deviation index [DI] and coefficient of variation [%CV]. The laboratory achieved 87.74% of values within acceptable limits for haemoglobin, 72.03% for white blood count, 69.49% for platelet and 77.03% for reticulocyte estimation. Results were satisfactory, having DI values less than 3 for all four parameters.%CV values was found to be dependent on the type of test performed and varied among different parameters. Difficulty has been observed in identifying Plasmodium malariae and ovale. Participation in External Quality Assessment Schemes is extremely beneficial for the improvement of laboratory performance and quality of care. Evaluation of the survey results on a regular basis serves as a useful guide to assess overall performance of the laboratory. Standardization of analytical procedures, equipments and reagents, continuous monitoring of personnel competency and thorough investigation of discordant results significantly contributes to the delivery of quality diagnostic services
Subject(s)
Humans , Hematology , Delivery of Health Care/standardsABSTRACT
To determine the validity of nalidixic acid screening test in the detection of high MICs of fluoroquinolone against Salmonella[S.] typhi isolated from blood and correlate zone diameters of ofloxacin with that of MIC value for nalidixic acid sensitive and resistant strains. Cross-sectional analytical study. Clinical Microbiology Laboratory of the Aga Khan Hospital, Karachi from January 2002 to December 2003. Two hundred S. typhi isolates from blood were included for nalidixic acid screening and ofloxacin susceptibility. Antibiotic susceptibilities for both the antibiotics were obtained by disc diffusion method whereas MICs were determined by standard agar dilution method as recommended by NCCLS guidelines. Sensitivity, specificity and correlation between both antimicrobial susceptibility methods were calculated and results expressed as scattergrams. The results broadly classify S. typhi isolates into nalidixic acid resistant strains with no zone of inhibition around 30 micro g nalidixic acid disc and nalidixic acid sensitive strains with mean zone of inhibition of 24.9mm. All S. typhi isolates with ofloxacin MIC of >/= 0.125 micro g/ml were found to be nalidixic acid resistant [MIC >/= 32 micro g/ml] whereas the isolates with ofloxacin MIC /= 0.125 micro g/ml]. Nalidixic acid resistance as a screening method is proved to be significant in identifying S. typhi isolates with reduced susceptibility to fluoroquinolones. It is also suggested that inhibition zone of