Comparison of real time polymerase chain reaction with microscopy and antigen detection assay for the diagnosis of malaria

To determine the sensitivity of a real time polymerase chain reaction [PCR] for malaria diagnosis and to compare its accuracy with microscopy and an antigen based rapid diagnostic test [OptiMal]. Cross-sectional analytical study. Military Hospital, Armed Forces Institute of Transfusion and Armed Forces Institute of Pathology, Rawalpindi, from July to December 2011. Venous blood samples of 300 clinically suspected patients of malaria were tested for malaria parasite by microscopy and OptiMal; and malaria parasite index was calculated for the positive samples. Plasmodium genus specific real time PCR was performed on all specimens, targeting small subunit rRNA gene. Diagnostic accuracy of three tests was compared and cost analysis was done. Out of 300 patients, malaria parasite was detected in 110, 106 and 123 patients by microscopy, OptiMAL and PCR respectively. Real time PCR was 100% sensitive while microscopy and OptiMal had sensitivity of 89.4% and 86.2% respectively. All methods were 100% specific. The cost per test was calculated to be 0.2, 2.75 and 3.30 US$ by microscopy, OptiMal and PCR respectively, excluding the once capital cost on PCR equipment. Genus specific real time PCR for the diagnosis of malaria was successfully established as a highly sensitive and affordable technology that should be incorporated in the diagnostic algorithm in this country.

Evaluation of stable coronary artery disease by multiple cardiac biomarkers

Effective management of stable coronary artery disease [SCAD] relies on early detection of coronary atherosclerosis. The objective was to evaluate diagnostic accuracy and risk stratification of SCAD patients by high sensitivity C reactive protein [hs CRP], Myeloperoxidase [MPO] and Pregnancy Associated Plasma Protein-A [PAPP-A]. validation study was conducted at Pathology Department of the Army Medical College, in collaboration with Armed Forces Institute of Cardiology [AFIC/NIHD] Rawalpindi. Total 122 subjects consisting of 61 patients of SCAD and 61 angio-negative controls were included. The levels of biomarkers were measured before angiography by using kits provided by Siemens [UK] for hs CRP and Abbott for MPO on Immulite 1000 and Architect Analyzer respectively, whereas serum PAPP-A was measured by an ELISA based method using kit provided by IBL Germany. The mean age of the patients was 56.57 +/- 8.35 years and consisted of 53 [86.9%] males and 8 [13%] females. Area under curve [AUC] and 95% CI of hs CRP 0.817 [0.736-.881] was significantly higher than that of MPO 0.685 [0.594-0.766] [p=0.018] and PAPP-A 0.565 [0.472-0.655] [p<0.001] for the diagnosis of SCAD. Patients in the highest quartile of PAPP-A were at the highest risk for adverse events as PAPP-A had the highest Hazard Ratio [HR] of 3.4 [p=0.004], as compared to hs CRP 1.124 [p=0.191] and MPO 0.998 [p=0.176]. hs CRP has superior diagnostic ability for detection of SCAD than MPO whereas PAPP-A is a more reliable marker for risk stratification among the cardiac biomarkers

Feasibility of short tandem repeats [STR] analysis for carrier detection and prenatal diagnosis in families with duchenne muscular dystrophy [DMD]

To determine the feasibility of Short tandem Repeats [STR] based linkage analysis for carrier detection and prenatal diagnosis [PND] in families having children affected with Duchemnne Muscular Dystrophy. Case series. Department of Chemical Pathology and Endocrinology in collaboration with Department of Molecular Biology, Armed Forces institute of Pathology [AFIP], Rawalpindi. From February 2007 to January 2008. six unrelated families with at least one affected child in each family who had characteristic features of DMD [index case]. PCR for Duchenne Muscular Dystrophy was carried out with STR based linkage analysis at introns 44, 46, 49 and 50 of DMD gene. Thermal cycling in TC-480 [Perkin Elmer] included 25 cycles each comprising 30 sec denaturation at 94 [degree sign] C, annealing at 62 [degree sign] C for 30 sec, extension at 65 [degree sign] C for 2 min. The final extension was done for 3 min. The amplified products were run on 8% nondenaturing polyacrylamide gel electrophoresis [PAGE] carried out at 200V for three hours on electrophoresis apparatus [Bio-Rad UK]. The gels were stained in silver nitrate. By comparing STR pattern of X-chromosome allele of index case with X-chromosome alleles of the mother, the diseased or affected X-chromosome was ascertained. Carrier detection and prenatal diagnosis was feasible with STR marker at intron 44 in DMD families. It was informative in 5 out of 6 DMD families. Carrier detection and PND by STR based linkage analysis is technically feasible in Pakistani families with DMD

Determination of glycosylated hemoglobin reference range in adult population attending a military care set up in Rawalpindi

To determine the glycosylated hemoglobin reference range in healthy adult population attending a military care setup in Rawalpindi in accordance with National Glycohemoglobin Standardization Program [NGSP] and International Federation of Clinical Chemistry [IFCC]. Descriptive cross-sectional study. Armed Forces Institute of Pathology Rawalpindi from May- Oct 2010. A total of 254 healthy adults [18-80 years] comprising 169 males and 85 females, were included by non probability consecutive sampling from Rawalpindi. History and clinical examination were carried out. Blood HbA1c was analyzed high performance liquid chromatography on biorad D-10. Data were analyzed by SPSS-17. Total 254 subjects consisting of 169 males and 85 females were recruited from Rawalpindi Pakistan. The reference range of total population was found 4.6-6.56% and 2.69-4.81 mmol/ mol in accordance with NGSP and IFCC, respectively. When compared in gender, HbA1c levels were not significantly changed. However, the healthy elderly population had higher HbA1c levels. Reference range for HbA1c based on NGSP in individuals <40 years was found 4.52-6.4% while for individuals aged > 40 years, it was 4.8-6.68%. The reference ranges for healthy individuals and the recommended values for optimal therapy in diabetic patients have to be revised and adjusted. Population based reference ranges should be established to provide better patient care services

Impact of CYP2C9 genetic polymorphism on warfarin dose requirements in Pakistani population

Variations of cytochrome-P450 enzyme system [CYP2CP] are associated with impaired metabolism of warfarin. The objective of our study was to estimate the frequency of genetic and allelic variants of CYP2C9 in Punjabi population of Pakistan and their effects on warfarin dose requirement. One hundred and twenty unrelated Pakistani subjects belong to Punjab province, were randomly included from the registry of National Institute of Heart Disease Rawalpindi, Pakistan. The patients had stable international normalized ratio [INR] of 2 to 3 for last 3 months with warfarin therapy after heart valves replacement. The detection of CYP2C9 variant was done on polymerase chain reaction-restriction fragment length polymorphism [PCR-RFLP] assay. Total 120 patients [73 males; 47 females] of mean age of 37 years participated in the study. Nine patients had mutant allele CYP2C9*3 [7.5%], one CYP2C9*2 [0.8%] and 110 patients exhibited wild type CYP2C9*1 [91.7%]. The frequency of CYP2C9 genotype was *1/*1 [0.858] ; *1/*3 [0.117] ; 2/*20 [0.08] and *3/*3 [0.017] in our study population. A high dose of warfarin [42.2 +/- 9.56] mg/week is required for patients with *1/*1 genotype as compared to patients with *2/*2 [17.5 +/- 1.9] and *1/*3 [16.6 +/- 2.3] allele [p<0.001]. Individuals with CYP2C9*3/3* need lowest [8.75 +/- 1.76 mg/week] daily warfarin dose. In conclusion, the genetic variations in the CYP2C9 occur in 14% of Punjabi ethnic group in Pakistan. Presence of CYP2C9*2 or *3 variants is an independent predictor of low warfarin dose requirement in our patients. CYP2C9 variants assay may be used in high risk groups for appropriate dose adjustment to avoid complications on long term basis

Significance of platelet indices in the diagnosis of immune thrombocytopenic purpura and aplastic anaemia

To compare the platelet indices in thrombocytopenia due to immune thrombocytopenic purpura and aplastic anaemia. This is observational study that was carried out from May 2006 to May 2007 at The Department of Haematology, Armed Forces Institute of Pathology [AFIP] and Armed Forces Bone Marrow Transplant Centre [AFBMTC], Rawalpindi. Seventy six [76] patients of thrombocytopenia were studied, of which 35 were patients of Immune thrombocytopenic purpura [ITP] and 41 patients of Aplastic anaemia [AA]. Platelet indices were measured on peripheral blood using automated haematology analyzer. Based on the bone marrow diagnosis, 35 patients of immune thrombocytopenic purpura and 41 patients of aplastic anaemia were studied. All indices were significantly higher in immune thrombocytopenic purpura than apiasiic anaemia. The mean MPV [Mean Platelet Volume] was 10.5fl in immune thrombocytopenic purpura and 8.6fl in aplastic anaemia [p <0.001], mean PDW [Platelet deviation width] was 15.6fl in immune thrombocytopenic purpura and 10.7fl in aplastic anaemia [p <0.001] and mean P-LCR [Platelet large cell ratio] was 31.2% in immune thrombocytopenic purpura and 17.7% in aplastic anaemia [p <0.001]. Our results suggest that these indices can provide reliable information to clinicians about the underlying etiology of thrombocytopenia and may help to avoid bone marrow examination, which is an invasive procedure, in some patients

Comparison of serum procalcitonin and c-reactive protein in diagnosis of bacterial meningitis

The diagnostic accuracy of Procalcitonin [PCT] as compared with C - reactive protein [CRP] for early diagnosis of bacterial meningitis in children was evaluated. Descriptive diagnostic study. This study was conducted in Pathology department of Army Medical College Rawalpindi from September 2007 to September 2008. Descriptive diagnostic accuracy study was conducted in Pathology Department of the Army Medical College, Rawalpindi. Total 77 subjects consisted of 31 patients of bacterial meningitis and 46 healthy children were included as controls from the Military hospital, Rawalpindi. The patients comprised of 18 [58%] male and 13 [42%] female with mean age 6 years. Patient's investigations including cerebrospinal fluid [CSF] examination and culture were carried out at admission. PCT and CRP were analyzed on Vidas analyzer and Immulite 1000 respectively. PCT levels were significantly high median [range] of 4.5 ng/ml [0.10-19.00] ng/ml than controls 0.45 ng/ml [0.10-3.00]. Serum CRP levels were moderately elevated with median [range] 11 mg /L [0.30 - 23.00] as compared with 0.30 mg/L [0.30-9.5] controls. The Area under receiver characteristic curve of PCT 0.86 [95% CI: 0.76-0.93] was significantly higher than CRP 0.72 [95% CI: 0.61-0.82]. The optimum diagnostic cutoff point for PCT and CRP were 2 ng/ ml and 6 mg/L respectively by ROC analysis. PCT had maximum sensitivity 74% and specificity 84% at cutoff > 2 ng/ ml while CRP revealed sensitivity 58% and specificity 83% at cutoff > 6mg/ L. This study has demonstrated PCT as a more reliable diagnostic marker than CRP for early diagnosis of bacterial meningitis and can be used in combination with clinical evaluation for proper management of the seriously ill children

Regulation of neuropeptide Y, vasoactive intestinal peptide and galanin by insulin in rats

To study the regulation of neuropeptide Y, vasoactive intestinal peptide and galanin by insulin in rats. Experimental study. The study was conducted at the department of Metabolic Medicine Hammersmith hospital, Royal Postgraduate Medical School, London for on year [1996-1997]. Tissue levels of neuro peptide Y [NPY] and vaso intestinal peptide [VIP] decreased of the intestine and pancreas in insulin infused rats. NPY was also decreased significantly in hypothalamus. No significant effect on NPY in brain stem and on VIP in hypothalamus was observed. Galanin decreased significantly in intestine and hypothalamus. Galanin mRNA decreased to 57.7 +/- 8.8 percent of controls [p < 0.05] in intestine and 58.7 +/- 17.7 percent of controls in hypothalamus. Therefore insulin decreased the tissue levels of galanin by inhibiting its mRNA. It is concluded that NPY, VIP and galanin are negatively regulated by insulin. Actions of insulin on endocrine pancreas and central control of glucose homeostasis and food intake by insulin may be partly modulated through changes in these peptides. VIP acts synergistically with glucagon in the development of hyperosmolar coma in NIDDM patients. NPY and galanin increase ketone bodies formation and hyperphagia in diabetics and contribute in the development of diabetic ketoacidosis and obesity

Reference value for high-sensitivity c-reactive protein in the northern pakistani population

High-sensitivity C-reactive protein [hS-CRP] is an acute phase protein that is often used for the risk estimation of cardiovascular diseases. Objective was to find out the reference range of hS-CRP in the healthy adult northern Pakistani population and compare the distribution in relation with age, gender, body mass index [BMI], ethnicity and smoking. Cross-sectional study. Army Medical College Rawalpindi from Nov 2007 - Mar 2009 In this cross-sectional study a total of 297 healthy adults [>18 years] comprising 207 males, 90 females, Punjabis [n=178] and Pathans [n=119] were randomly included from Rawalpindi, Lahore, Peshawar and Sawabi Districts. History and clinical examination were carried out. Serum hS-CRP was analysed in Clinical Pathology Laboratory, Army Medical College Rawalpindi by two site sequential chemiluminiscent immunometric assay kit on immulite 1000 [USA]. Data were analysed by SPSS-16. The reference values for hS-CRP are presented as median [2.5 th - 97.5 th percentile]. In the healthy adult population of Northern Pakistan it was 1.84 mg/L [0.37-4.81] mg/l; in Punjabis 1.75 [0.30-4.65] mg/l and in Pathans 1.93 [0.50-5.30] mg/l. Females had higher hS-CRP levels 2.05 [0.53-5.66] mg/l as compared to the males 1.76 [0.31-5.06] mg/l. Smokers had relatively higher hS-CRP 1.98 mg/l [0.47-5.56] mg/l than non-smokers 1.68 mg/l [0.30-4.60]. Our data also revealed that hS-CRP had significant positive correlation with advancing age [r=0.20;p<0.05] and increasing BMI [r=0.29;p<0.01]. The reference range for hS-CRP in the population of Northern Pakistan is 0.37-4.81 mg/l. Pathans have higher hS-CRP levels than Punjabis. Demographic factors including age and BMI were positively correlated to the distribution of hS-CRP

Evaluation of post challenge Glucose Estimation For Diagnosis of Gestational Diabetes Mellitus [W.H.O. - Criteria 1999]

To compare sensitivity, specificity and Positive Predictive Value [PPV] and Negative Predictive Value [NPV] of 75g Oral Glucose Tolerance Test [OGTT] i.e. WHO criteria 1999 with 100g OGTT of National Diabetes Data Group [NDDG criteria]. Study Design: Comparative cross sectional. Material and Methods:The study was conducted at Department of Chemical Pathology and Endocrinology, Armed Forces Institute of Pathology [AFIP], Rawalpindi. Duration of study: 1st January 2004 to 31st August 2004. Sample size: Approx one hundred pregnant ladies between 24 to 28 gestational weeks. Sampling technique: Non-probability convenience. Data collection procedure: Patients consent for participation in the study was taken with explanation of test procedure. Patient's characteristics such as age, obesity, family history of diabetes, pregnancy induced hypertension, previous bad obstetric history [of still birth, macrosomia, recurrence abortion] was recorded on a predesigned proforma. Patients were first called for 75g OGTT and then after a gap of 1-2 days for OGTT 100g. Both tests were performed according to standard protocols. OGTT 75g was found to have 87.5% sensitivity, 97.8% specificity, and 77.7% positive predictive value and 98.8% negative predictive value, when compared with 100g OGTT