Molecular surveillance of putative drug resistance markers of antifolate and artemisinin among imported Plasmodium falciparum in Qatar.

Malaria remains a significant public health challenge and is of global importance. Imported malaria is a growing problem in non-endemic areas throughout the world and also in Qatar due to a massive influx of migrants from endemic countries. Antimalarial drug resistance is an important deterrent in our fight against malaria today. Molecular markers mirror intrinsic antimalarial drug resistance and their changes precede clinical resistance. Thus, in the present study, molecular markers of sulphadoxine-pyrimethamine (Pfdhfr and Pfdhps) and artemisinin (PfATPase6 and Pfk13) were sequenced to determine the drug resistance genotypes among 118 imported P. falciparum isolates in Qatar, between 2013 and 2016. All the isolates had mutant Pfdhfr alleles, with either double mutant (51I/108N) (59.3%) or triple mutant (51I, 59R and 108N) (30.6%) genotypes. I164L substitution was not found in this study. In case of Pfdhps, majority of the samples were carriers of either single (S436A/ A437G/ K540E) mutant (47.2%) or double (S436A/K540E, A437G/K540E, K540E/A581G) mutant (39.8%). A single novel point mutation (431V) was observed in the samples originated from Nigeria and Ghana. Polymorphisms in PfATPase6 were absent and only one non-synonymous mutation in Pfk13 was found at codon G453A from a sample of Kenyan origin. High levels of sulphadoxine-pyrimethamine resistance in the present study provide potential information about the spread of antimalarial drug resistance and will be beneficial for the treatment of imported malaria cases in Qatar.

Distribution of Mutations Associated with Antifolate and Chloroquine Resistance among Imported Plasmodium vivax in the State of Qatar.

Plasmodium vivax is the most prevalent parasite worldwide, escalating by spread of drug resistance. Currently, in Qatar, chloroquine (CQ) plus primaquine are recommended for the treatment of P. vivax malaria. The present study examined the prevalence of mutations in dihydrofolate reductase (dhfr), dihydropteroate synthase (dhps) genes and CQ resistance transporter (crt-o) genes, associated with sulphadoxine-pyrimethamine (SP) and chloroquine resistance, among imported P. vivax cases in Qatar. Blood samples were collected from patients positive for P. vivax and seeking medical treatment at Hamad General Hospital, Doha, during 2013-2016. The Sanger sequencing method was performed to examine the single nucleotide polymorphisms in Pvdhfr, Pvdhps, and Pvcrt-o genes. Of 314 examined P. vivax isolates, 247 (78.7%), 294 (93.6%) and 261 (83.1%) were successfully amplified and sequenced for Pvdhfr, Pvdhps, and Pvcrt-o, respectively. Overall, 53.8% (N = 133) carried mutant alleles (58R/117N) in Pvdhfr, whereas 77.2% (N = 227) and 90% (N = 235) isolates possessed wild type allele in Pvdhps and Pvcrt-o genes, respectively. In addition, a total of eleven distinct haplotypes were detected in Pvdhfr/Pvdhps genes. Interestingly, K10 insertion in the Pvcrt-o gene was observed only in patients originating from the Indian subcontinent. The results suggested that CQ remains an acceptable treatment regimen but further clinical data are required to assess the effectiveness of CQ and SP in Qatar to support the current national treatment guidelines. In addition, limited distribution of genetic polymorphisms associated with CQ and SP resistance observed in imported P. vivax infections, necessitates regular monitoring of drug resistant P. vivax malaria in Qatar.

Computed tomography abnormalities and epidemiology of adult patients presenting with first seizure to the emergency department in Qatar.

OBJECTIVES: There is little information available from the Middle Eastern region on adult patients presenting with first seizure. The objectives of this study were to describe epidemiological characteristics of patients presenting to the emergency department (ED) in Doha, Qatar, with first seizure and to determine the incidence of computed tomographic (CT) scan abnormalities. METHODS: A retrospective cohort study was conducted on all adult patients with first seizure presenting to Hamad General Hospital ED over a 1-year period (June 2012 through May 2013). Electronic patient records were reviewed for demographics, neuroimaging, electroencephalography, laboratory test results, and medications administered. RESULTS: There were 439 patients who satisfied inclusion criteria. Patients were aged a mean of 35.3 years (95% confidence interval [CI] = 33.92 to 36.69 years) with a male-to-female ratio of five to one. CT abnormalities were detected in 154 patients (35.3%; 95% CI = 30.81% to 39.82%). Out of reported abnormal scans, 14.7% patients had significant abnormalities such as neurocysticercosis (9.2%); brain metastasis and neoplasm (3.4%); and subarachnoid and subdural hemorrhage, cavernous sinus thrombosis, acute stroke, and brain edema (2.0%). None of the patients had any electrolyte abnormalities, and three patients had hypoglycemia. Patients with initial abnormal CT brain results were more likely to have recurrent seizures (OR = 1.65; 95% CI = 1.11 to 2.45) within 6 months. CONCLUSIONS: Adults who presented with first seizure to the ED in Qatar had a young male predominance, and a high proportion of brain CT scans were reported as abnormal. It is recommended that all such patients in this population should undergo prompt CT scanning in the ED, but the utility of routine electrolyte tests requires further investigation.