Genetic diversity of Plasmodium vivax clinical isolates from southern Pakistan using pvcsp and pvmsp1 genetic markers

Background: Plasmodium vivax is the prevalent malarial species accounting for 70% of malaria burden in Pakistan; however, there is no baseline data on the circulating genotypes. Studies have shown that polymorphic loci of gene encoding antigens pvcsp and pvmsp1 can be used reliably for conducting molecular epidemiological studies. Therefore, this study aimed to bridge the existing knowledge gap on population structure on P. vivax from Pakistan using these two polymorphic genes. Methods: During the period January 2008 to May 2009, a total of 250 blood samples were collected from patients tested slide positive for P. vivax, at the Aga Khan University Hospital, Karachi, or its collection units located in Baluchistan and Sindh Province. Nested PCR/RFLP was performed, using pvcsp and pvmsp1 markers to detect the extent of genetic diversity in clinical isolates of P. vivax from southern Pakistan. Results: A total of 227/250 (91%) isolates were included in the analysis while the remainder were excluded due to negative PCR outcome for P.vivax. Pvcsp analysis showed that both VK 210 (85.5%, 194/227) and VK 247 type (14.5%, 33/227) were found to be circulating in P. vivax isolates from southern Pakistan. A total of sixteen and eighty-seven genotypes of pvcsp and pvmsp-1 were detected respectively. Conculsion: This is the first report from southern Pakistan on characterization of P. vivax isolates confirming that extensively diverse pvcsp and pvmsp1 variants are present within this region. Results from this study provide valuable data on genetic diversity of P. vivax that will be helpful for further epidemiological studies

Neurological complications in patients with plasmodium vivax malaria from Karachi, Pakistan

Background: Malaria remains an endemic disease in Pakistan with an estimated healthcare burden of 1.6 million cases annually, with Plasmodium vivax accounting for 67% of reported cases. P. vivax is the most common species causing malaria outside of Africa, with approximately 13.8 million reported cases worldwide. Method: We report a series of P. vivax cases with cerebral involvement that presented at Aga Khan University Hospital, Karachi, Pakistan. Results: The majority of the patients presented with high-grade fever accompanied by projectile vomiting and abnormal behaviour, seizures, shock and unconsciousness. Seven of 801 patients with P. vivax monoinfection presented or developed cerebral complications. P. vivax infections were diagnosed based on peripheral smears and rapid diagnostic testing. Conclusion: P. vivax infection can lead to severe complications, although not with the frequency of Plasmodium falciparum infection. Current cases highlight an increasing trend of cerebral complications caused by P. vivax

Genetic diversity among Plasmodium falciparum field isolates in Pakistan measured with PCR genotyping of the merozoite surface protein 1 and 2

Background:The genetic diversity of Plasmodium falciparum has been extensively studied in various parts of the world. However, limited data are available from Pakistan. This study aimed to establish molecular characterization of P. falciparum field isolates in Pakistan measured with two highly polymorphic genetic markers, i.e. the merozoite surface protein 1 (msp-1) and 2 (msp-2).Methods:Between October 2005 and October 2007, 244 blood samples from Patients with symptomatic blood-slide confirmed P. falciparum mono-infections attending the Aga Khan University Hospital, Karachi, or its collection units located in Sindh and Baluchistan provinces, Pakistan were collected. The genetic diversity of P. falciparum was analysed by length polymorphism following gel electrophoresis of DNA products from nested polymerase chain reactions (PCR) targeting block 2 of msp-1 and block 3 of msp-2, including their respective allelic families KI, MAD 20, RO33, and FC27, 3D7/IC.Results:A total of 238/244 (98%) Patients had a positive PCR outcome in at least one genetic marker, the remaining six were excluded from analysis. A majority of Patients had monoclonal infections. Only 56/231 (24%) and 51/236 (22%) carried multiple P. falciparum genotypes in msp-1 and msp-2, respectively. The estimated total number of genotypes was 25 msp-1 (12 KI, 8 MAD20, 5 RO33) and 33 msp-2 (14 FC27, 19 3D7/IC).Conclusion:This is the first report on molecular characterization of P. falciparum field isolates in Pakistan with regards to multiplicity of infection. The genetic diversity and allelic distribution found in this study is similar to previous reports from India and Southeast Asian countries with low malaria endemicity

Prevalence of resistance associated polymorphisms in Plasmodium falciparum field isolates from southern Pakistan

<p>Abstract</p> <p>Background</p> <p>Scarce data are available on <it>Plasmodium falciparum </it>anti-malarial drug resistance in Pakistan. The aim of this study was, therefore, to determine the prevalence of <it>P. falciparum </it>resistance associated polymorphisms in field isolates from southern Pakistan.</p> <p>Methods</p> <p>Blood samples from 244 patients with blood-slide confirmed <it>P. falciparum </it>mono-infections were collected between 2005-2007. Single nucleotide polymorphisms in the <it>P. falciparum </it>chloroquine resistance transporter (<it>pfcrt </it>K76T), multi drug resistance (<it>pfmdr1 </it>N86Y), dihydrofolate reductase (<it>pfdhfr </it>A16V, N51I, C59R, S108N, I164L) and dihydropteroate synthetase (<it>pfdhps </it>A436S, G437A and E540K) genes and <it>pfmdr1 </it>gene copy numbers were determined using PCR based methods.</p> <p>Results</p> <p>The prevalence of <it>pfcrt </it>76T and <it>pfmdr1 </it>86Y was 93% and 57%, respectively. The prevalence of <it>pfdhfr </it>double mutations 59R + 108N/51R + 108N was 92%. The <it>pfdhfr </it>triple mutation (51I, 59R, 108N) occurred in 3% of samples. The <it>pfdhfr </it>(51I, 59R, 108N) and <it>pfdhps </it>(437G, 540E) quintuple mutation was found in one isolate. <it>Pfdhps </it>437G was observed in 51% and 540E in 1% of the isolates. One isolate had two <it>pfmdr1 </it>copies and carried the <it>pfmdr1 </it>86Y and <it>pfcrt </it>76T alleles.</p> <p>Conclusions</p> <p>The results indicate high prevalence of <it>in vivo </it>resistance to chloroquine, whereas high grade resistance to sulphadoxine-pyrimethamine does not appear to be widespread among <it>P. falciparum </it>in southern Pakistan.</p

Vivax malaria and chloroquine resistance: a neglected disease as an emerging threat

In Pakistan, Plasmodium vivax contributes to major malaria burden. In this case, a pregnant woman presented with P. vivax infection and which was not cleared by chloroquine, despite adequate treatment. This is probably the first confirmed case of chloroquine-resistant vivax from Pakistan, where severe malaria due to P. vivax is already an emerging problem

Diagnostic Value of Gauze Filtration Technique: A Comparison with Conventional Methods in a Diagnostic Laboratory in Pakistan

Background: Intestinal parasites cause significant morbidity and impact human development with an enormous global burden. Diagnosis of intestinal parasites by conventional methods has several limitations. The gauze filtration technique is a relatively simple method that has been shown to identify intestinal parasites with a high sensitivity and specificity. The aim of this study was to determine the diagnostic value of this technique as compared to more conventional methods in a large acclaimed laboratory within Pakistan. Methods: A total of 50 stool samples collected for routine diagnostic workup from patients age between 2-70 years were collected from the parasitology section of the Aga Khan University Hospital Clinical Laboratory. A direct wet mount, sedimentation technique, and gauze filtration technique were performed on all of the stool samples, and the sensitivity, specificity, negative predictive value, and positive predictive value were analyzed. Results: It was observed that the number of organisms observed by gauze filtration as compared to direct wet mount and sedimentation technique was higher for B. hominis, G. lamblia cysts and trophozoites, and I. bütschlii. Also, the detection rate was significantly higher for B. hominis and G. lamblia cysts using the gauze filtration technique. The sensitivity and specificity of the gauze filtration technique were found to be 95.8% and 100%, respectively. Conclusion: There is a significantly better stool sample parasite detection rate using the gauze filtration technique as compared to the conventional sedimentation techniques. The utility of the gauze filtration technique seems economically and technically feasible for diagnostic laboratories in resource-limited settings

Hematological profile and gametocyte carriage in malaria patients from southern Pakistan

Background: Malarial infection is a major cause of concern, both worldwide and in Pakistan. Gametocytes are the sexual forms of the parasite that are essential for transmission. They fuse inside the mosquito to develop sporozoites. Gametocytes of the plasmodium parasites, which cause the infection, differentiate into male and female gametocytes. These gametocytes constitute the sexual stage of the malaria parasite and are essential in transmission of the disease from human to vector Anopheles. Gametocytes are affected by factors such as host immunity, drug treatment, reticulocytemia, anemia, low levels of asexual parasitemia and stress to the parasite. The aim of this study was to observe the hematological parameters, age and gametocyte carriage in an area of seasonal malaria transmission.Methods: The study was conducted at Aga Khan University Hospital (AKUH) Laboratory over the period of one year and 294 patients with uncomplicated malaria were recruited. Patients infected with Plasmodium falciparum (P. falciparum) or Plasmodium vivax (P. vivax) malaria and no co-morbidities were included in the study.Results: Gametocytemia was highest during the period of July to November, with P. vivax, 267 (90.8%), predominating compared to P. falciparum, 27 (9.2%). P. vivax gametocytes were observed from May to October and P. falciparum gametocytes were observed from July to December. Low hemoglobin in females and low platelet levels were observed. The mean platelet count was significantly lower in cases of P. vivax having gametocytes compared to P. falciparum with gametocytes. Higher parasitic index was associated with lower platelet count. The most significantly altered parameters were hemoglobin, hematocrit, white blood cell (WBC), and platelet count. Hemoglobin and platelets were significantly lower during the malaria season in study participants, both male and female.Conclusion: In conclusion, infection with P. falciparum and P. vivax modulates significant changes in hematological parameters in populations living in malaria endemic regions. In the malaria season males were more frequently affected by malaria with thrombocytopenia. Gametocyte carriage remains unaffected by seasonal changes thus ensuring parasite transmission during the dry season

Action on diabetic macular oedema: achieving optimal patient management in treating visual impairment due to diabetic eye disease

This paper identifies best practice recommendations for managing diabetes and sight-threatening diabetic eye disease. The authors provide an update for ophthalmologists and allied healthcare professionals on key aspects of diabetes management, supported by a review of the pertinent literature, and recommend practice principles for optimal patient management in treating visual impairment due to diabetic eye disease. In people with diabetes, early optimal glycaemic control reduces the long-term risk of both microvascular and macrovascular complications. The authors propose more can and should be done to maximise metabolic control, promote appropriate behavioural modifications and encourage timely treatment intensification when indicated to ameliorate diabetes-related complications. All people with diabetes should be screened for sight-threatening diabetic retinopathy promptly and regularly. It is shown that attitudes towards treatment adherence in diabetic macular oedema appear to mirror patients' views and health behaviours towards the management of their own diabetes. Awareness of diabetic macular oedema remains low among people with diabetes, who need access to education early in their disease about how to manage their diabetes to delay progression and possibly avoid eye-related complications. Ophthalmologists and allied healthcare professionals play a vital role in multidisciplinary diabetes management and establishment of dedicated diabetic macular oedema clinics is proposed. A broader understanding of the role of the diabetes specialist nurse may strengthen the case for comprehensive integrated care in ophthalmic practice. The recommendations are based on round table presentations and discussions held in London, UK, September 2016

Diagnostic Accuracy of Monitoring Tests of Fellow Eyes in Patients with Unilateral Neovascular Age-Related Macular Degeneration : Early Detection of Neovascular Age-Related Macular Degeneration Study

Funding Information: The author(s) have made the following disclosure(s): R.G.: Personal fees ? Heidelberg Engineering.S.S.: Grants and personal fees ? Bayer, during the conduct of the study; Grants and personal fees ? Novartis, Boehringer Ingleheim; Grants ? Allergan, Roche; Personal fees ? Apellis, Oxurion, Heidelberg Engineering, Optos, outside the submitted work; Funded by the Moorfields Biomedical Research Centre and Clinical Research Facility.The project was funded by the National Institute for Health Research Health Technology Assessment Programme (Project Number: 12/142/07) and will be published in full in Health Technology Assessment. The Health Services Research Unit and the Health Economics Research Unit are core funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorate. F.G.: Grants ? NIHR, during the conduct of the study; Grants and personal fees ? Novartis, Roche, Bayer; Personal fees ? Allergan, Alimera; Grants ? Chengdu Pharma; Grants and nonfinancial support ? NIHR, outside the submitted work. J.A.C.: Study grant ? NIHR. K.B.: Grants ? NIHR HTA Programme, during the conduct of the study. Obtained funding: Chakravarthy, Ramsay, Sivaprasad, Scotland, Azuara-Blanco, Heiman and Cook Publisher Copyright: © 2021Peer reviewedPublisher PD