Aliehsan Heidari

Genotypes and in vivo resistance of Plasmodium falciparum isolates in an endemic region of Iran.

Mutations in the dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) genes of Plasmodium falciparum have been correlated with and used to detect antifolate treatment failure, such as sulfadoxine–pyrimethamine (SP), in regions endemic for malaria. To determine the association between molecular markers of SP resistance and in vivo drug resistance, a quick and simple technique that detects single nucleotide polymorphisms in the DHFR and DHPS genes, using PCR–ELISA and sequence-specific oligonucleotide probes, was applied to 53 isolates obtained from an in vivo study in Sistan and Baluchistan Province, in southeastern Iran. Overall, 11.3% of these isolates were obtained from patients with SP treatment failure. Four DHFR polymorphisms (codons 51, 59, 108, and 164) and five DHPS polymorphisms (codons 436, 437, 540, 581, and 613) were investigated. Mutations DHFR Asn-108, DHFR Arg-59, and DHPS 436-Ala/Phe were very common (100, 81.1, and 85%, respectively). Plasmodium falciparum was isolated from 96% of patients with at least two DHFR/DHPS mutations. All resistant isolates had at least three mutations. The high prevalence of mutation associated with antifolate resistance may point toward low drug efficacy in the future.

Genetic diversity and natural selection at the domain I of apical membrane antigen-1 (AMA-1) of Plasmodium falciparum in isolates from Iran

The apical membrane antigen-1 (AMA-1) of Plasmodium falciparum is a prime malaria asexual blood-stage vaccine candidate. Antigenic variation is one of the main obstacles in the development of a universal effective malaria vaccine. The extracellular region of P. falciparum AMA-1 (PfAMA-1) consists of three domains (I-III), of which the domain I is the most diverse region of this antigen. The objective of our study was to investigate and analyze the extent of genetic diversity and the effectiveness of natural selection at the AMA-1 domain I of P. falciparum in isolates from Iran. A fragment of ama-1 gene spanning domain I was amplified by nested PCR from 48 P. falciparum isolates collected from two major malaria endemic areas of Iran during 2009 to August 2010 and sequenced. Genetic polymorphism and statistical analyses were performed using DnaSP and MEGA software packages. Analysis of intrapopulation diversity revealed relatively high nucleotide and haplotype diversity at the PfAMA-1 domain I of Iranian isolates. Neutrality tests provided strong evidence of positive natural selection acting on the sequenced gene region. The findings also demonstrated that, in addition to natural selection, intragenic recombination may contribute to the diversity observed at the domain I. The results obtained will have significant implications in the design and the development of an AMA-1-based vaccine against falciparum malaria.

Detection of mixed-species infections of Plasmodium falciparum and Plasmodium vivax by nested PCR and rapid diagnostic tests in southeastern Iran.

Coexistence of two species of Plasmodium in a single host has disrupted the diagnosis and treatment of malaria. This study was designed to evaluate the ability of rapid diagnostic test (RDT) kits for the diagnosis of mixed-species malaria infections in southeastern Iran. A total of 100 malaria patients were included in the study out of 164 randomly suspected symptomatic malaria patients from May to November 2012. Nested polymerase chain reaction (PCR) was also used to judge the ability of microscopy versus RDT kits for detecting mixed species. The sensitivity of light microscopy for the detection of mixed-species malaria infections was 16.6% (95% confidence interval [CI] = 3-49.1). Nested PCR revealed 12 patients with mixed-species infection. The CareStart Pv/Pf Combo kit detected 58% of the mixed-species infections, which were determined by nested PCR (sensitivity = 58.3%; 95% CI = 28.5-83.5). For identifying P. falciparum, P. vivax, and mixed-species infections, the concordance rates (kappa statistics) of microscopy and CareStart Pv/Pf Combo kit with nested PCR were 0.76 and 0.79, respectively (P = 0.001). This study underlines the effectiveness of RDT kits to improve the differentiation of mixed-species malaria infections in endemic areas where the prevalence of chloroquine resistance is high.

Genetic polymorphism at the C-terminal domain (region III) of knob-associated histidine-rich protein (KAHRP) of Plasmodium falciparum in isolates from Iran

The knob-associated histidine-rich protein (KAHRP) plays a major role in the virulence of Plasmodium falciparum and is one of the targets for molecular therapy. The primary structure of KAHRP of P. falciparum consists of three domains (regions I–III), of which the C-terminal domain (region III) is the most polymorphic segment of this protein. One of the main obstacles is genetic diversity in designing and developing of malaria control strategies such as molecular therapy and vaccines. The primary objective of the present study was to investigate and analyze the extent of genetic polymorphism at the region III of KAHRP of P. falciparum in isolates from Iran. A fragment of the kahrp gene spanning the C-terminal domain was amplified by nested PCR from 50 P. falciparum isolates collected from two malaria endemic areas of Iran during 2009 to August 2010 and sequenced. In this study, three allelic types were observed at the C-terminal domain of KAHRP on the basis of the molecular weight of nested PCR products and the obtained sequencing data. The presence of multiple alleles of the kahrp gene indicates that several P. falciparum strains exist in the malaria endemic areas of Iran. Our findings will be valuable in the design and the development of the molecular therapeutic reagents for falciparum malaria.

Visceral Leishmaniasis in Rural Areas of Alborz Province of Iran and Implication to Health Policy.

Visceral leishmaniasis (VL) or kala-azar mainly affects children in endemic areas. This study was conducted to determine the seroprevalence of VL using direct agglutination test (DAT) in children living in rural districts of Alborz Province located 30 km from Tehran capital city of Iran. Multi-stage cluster random sampling was applied. Blood samples were randomly collected from 1,007 children under 10 years of age in the clusters. A total of 37 (3.7%) of the studied population showed anti-Leishmania infantum antibodies with titers of ≥1:800. There was a significant association between positive sera and various parts of the rural areas of Alborz Province (P<0.002). Two children with anti-Leishmania infantum antibodies titers of ≥1:3,200 indicated kala-azar clinical features and treated with anti-leishmaniasis drugs in pediatric hospital. The findings of this study indicated that Leishmania infection is prevalent in rural areas of Alborz Province. Therefore, it is necessary to increase the awareness and alertness among physicians and public health managers, particularly in high-risk rural areas of the province in Iran.

Plasmodium vivax population structure in malaria endemic area of southern Iran

PURPOSE To investigate the clinical characteristics, laboratory features and prognostic factors of elderly patients with postneurosurgical bacterial meningitis. METHODS Five hundred and forty patients with adult bacterial meningitis (ABM) were collected from 1986-2015, of whom 167 were ≥ 65 years. Of these 167 elderly patients, 82 had postneurosurgical infections and 85 had spontaneous infections. Clinical, laboratory and therapeutic data of these two groups were compared. RESULTS The 82 elderly ABM patients with postneurosurgical infections included 48 men and 34 women with a median age of 71 years (range: 65-84 years). In addition to the postneurosurgical condition, the other most common underlying conditions included diabetes mellitus (29.3%) and hydrocephalus (29.3%). The major clinical presentations were fever (80.5%), altered consciousness (50.0%), hydrocephalus (43.9%), seizure (24.4%) and septic shock (15.9%). Of the implicated pathogens, staphylococcal species (spp.) were the most common (31.7%), followed by Acinetobacter spp. (12.2%), Enterobacter spp. (7.3%), Pseudomonas spp. (7.3%), Enterococcus faecalis (7.3%) and Escherichia coli (6.1%). The implicated staphylococcal spp. had a high rate of non-susceptibility to methicillin (84.6%), and the implicated Acinetobacter spp. and Enterobacter spp. had non-susceptible rates to ceftazidime of 60% and 50%, respectively. The mortality rate was 28.1%, and septic shock was the most significant prognostic factor. Compared with the clinical characteristics of the other 85 elderly patients with spontaneous ABM, there were significant differences in underlying condition, clinical and laboratory features and therapeutic outcomes. CONCLUSIONS Elderly patients accounted for 30.9% of all cases of ABM, of whom 49.1% had postneurosurgical ABM. The clinical characteristics of the elderly patients with postneurosurgical ABM were non-specific, and cerebrospinal fluid studies were needed to confirm the diagnosis. The mortality rate of this group of patients was high, and septic shock was an important prognostic factor. The clinical and laboratory features and therapeutic outcomes were different between the elderly patients with postneurosurgical and spontaneous ABM.L fluke is an endemic in Southeast Asia particularly in Thailand, Lao People’s Democratic Republic, and Cambodia. The infection is associated to cholangiocarcinoma; bile duct cancer. Prevention and control is required to decrease the liver fluke incident. Here, we described the liver fluke prevention and control program (LFPCP) through Interand Transdisciplinary University (ITU). LFPCP was constructed among the rural communities in northeast Thailand during November 2016 and July 2017. ITU was integrated in LFPCP; briefly, ITU is comprised the partnership, scholarship, mutual benefit, and social impact. ITU is established by teachers and student (medical, nursing, public health, engineering, and business computer) from Suranaree University of Technology, Vongchavalitkul University, and Nakhon Ratchasima Rajabhat University, local government officers, and villagers, to solve the health problem in the rural community particularly liver fluke disease and cholangiocarcinoma. Quantitative and qualitative data were collected by questionnaires, group and individual feedback, consequently. Of 120 participants were included. Participants (89%) had a high level of satisfaction regarding LFPCP particularly in the steps of sharing ideas, decision making, and planning step. They could improve their knowledge, attitude and their practice regarding liver fluke prevention and control. LFPCP is an integrative activity that improves knowledge, attitude, skill, and practice for students and villagers. Therefore, LFPCP toward ITU is highly potential mutual benefit among university, students, teachers, and communities.C difficile is not only the most common organism to cause hospital acquired infections in the US but the incidence in cancer patients is increasing significantly. Their risk factors for acquiring Clostridium difficile infections (CDI) are prolonged hospitalization, chemotherapy, and changes in bowel environment. However, the most common risk is frequent exposure to antibiotics. The centers for disease control and prevention showed the risk of CDI among those exposed to highrisk antibiotics was three times higher compared to persons with low-risk or no antibiotic exposure. This emphasizes the crucial role of ASPs which have created a positive impact on CDI rates in several studies. At a private oncology hospital, ASP and infection control use several strategies to retain low rates of CDI. ASP reviews all patients on antibiotics daily to identify opportunities to optimize therapy. Prospective audit and feedback is then provided to clinicians on any necessary interventions. Educational in-services are also performed for nurses and the medical staff on a regular basis. Additionally, infection control enforces strict hand hygiene for which compliance has consistently been greater than 98%. Due to oncology patients having a higher incidence of baseline diarrhea, a three-component C. difficile test is used at this institution to reduce false positive results. The glutamate dehydrogenase (GDH) antigen and enzyme immunoassay tests for toxins A and B are obtained on all samples. If there is discordance between the tests, then only is a polymerase chain reaction (PCR) test performed. With these combined efforts, there were 0 incidences of CDI over a period of 10 months in 2017 and no more than one incidence per month since January of 2016. However, both incidences in August and September 2017 were false positive results. Therefore, without any clinical infections, the institution had 0 incidences of CDI for one year (table 1).Crimean-Congo hemorrhagic fever (CCHF) is an arboviral zoonotic infection wich is endemic in some areas of the country. The aim of this study was to assess the seroprevalence of CCHFV in previous and recent endemic areas of the country. This crosssectional serologic study was conducted in period 20102014 by the Institute of Public health in Tirana, Albania. The survey included 152 sera specimen of cattle which were randomly collected from seven districts in Albania over the period 2010-2014. All samples were collected randomly from seven districts in Albania and were examined for anti-CCHFV IgG. Of the total of 152 samples examined, 102 (67.1%) were positive to IgG ELISA. The highest positivity rate was among cows (88.3%) and in recent endemic areas of Has and Kukes, 89.7% and 82.9% respectively. In recent endemic areas humans can potentially contract the disease as compared to other areas of the country.

Therapeutic efficacy of chloroquine and primaquine for Plasmodium vivax malaria treatment in southeast Iran

Background Plasmodium vivax is the main cause of malaria infection in Asian, Central and South American countries [1]. It accounts for more than 90% annually of the reported malaria cases in Iran [2]. Plasmodium vivax resistant to chloroquine has emerged in some regions of Asia and resistance or tolerance to primaquine has been demonstrated in several countries [3,4]. The aim of this study was to determine the therapeutic efficacy of chloroquine and primaquine for Plasmodium vivax malaria treatment in southeast Iran.