Should pyridoxine be given to breastfed infants whose mothers are on isoniazid? Khuen Foong Ng, Srini Bandi Asian Pacific Journal of Tropical Medicine 2019 12(10):435-437

Glycemic control in tuberculosis: Lessons learned from Taiwan Min-Chih Wang, Jorge Cervantes Asian Pacific Journal of Tropical Medicine 2019 12(10):438-441 The global epidemic of diabetes and tuberculosis poses challenges to the control of both diseases. Patients with tuberculosis and diabetes experience worse clinical manifestations, increased risk of treatment failure, recurrence, and death. Diabetes is also associated with risk for latent tuberculosis infection. Management of hyperglycemia reduces the risk and improves the outcome of tuberculosis in diabetic patients. Recent epidemiological studies from Taiwan have provided new and important information on the benefits of metformin in tuberculosis. When addressing the issue of multidrug-resistant tuberculosis, a shortened anti-tuberculous therapeutic regime seems a feasible approach for better cure rates, with less loss-to-follow.

Manifestations and outcomes of leptospirosis during local outbreaks in high endemic districts of Sri Lanka: A retrospective multi-center study Thilini Nisansala, Kanchana Bandara, Manjula Weerasekera, Chinthika Gunasekara, Chamil Marasinghe, Chandika D Gamage, Neluka Fernando, Nilantha Ranasinghe Asian Pacific Journal of Tropical Medicine 2019 12(10):442-449 Objective: To determine the clinical presentations and disease outcomes of suspected and confirmed cases of leptospirosis from 3 high endemic districts of Sri Lanka, during outbreaks reported between 2013 and 2017. Methods: The retrospective multi-center study was carried out during 2013-2017 in 5 selected hospitals representing 3 high endemic districts in Sri Lanka. Clinically suspected leptospirosis patients were recruited according to the Communicable Disease Epidemiology Profile Sri Lanka, WHO. Leptospirosis was confirmed by either single microscopic agglutination test titre 1: 400 or by positive polymerase chain reaction (PCR) test result. Results: Out of 372 clinically suspected cases, 29.00% were confirmed as leptospirosis cases by either microscopic agglutination test (50.00%) or positive polymerase chain reaction (52.77%) and 12.90% were presumptively identified as leptospirosis. Clinical symptoms (headache, vomiting, jaundice and dyspnoea) and variations in haematological parameters (haemoglobin, platelet count) and biochemical parameters (serum creatinine, serum urea, serum bilirubin and C-reactive protein) were associated with confirmed leptospirosis (P<0.05). Acute kidney injury, meningitis, myocarditis, pulmonary haemorrhage and acute liver failure was seen among 21.30%, 12.04%, 6.48%, 6.48%, 5.56%, respectively with 4.63% fatality among the leptospirosis confirmed patients. The sensitivity, specificity, positive predictive value and negative predictive value of the case definition of Ministry of Health, Sri Lanka were 96.29%, 9.09%, 31.13%and 85.71%, respectively, when benchmarked against either positive polymerase chain reaction or microscopic agglutination test as the gold standard. Conclusions: Acute kidney injury is the predominant complication observed among the leptospirosis confirmed patients. However, pulmonary haemorrhage is predominantly associated with mortality. The case definition of Ministry of Health, Sri Lanka is found to have higher sensitivity and enabled the screening of all probable cases of leptospirosis.

Molecular characterization and subtyping of Blastocystis in urticarial patients in Turkey Merve Aydin, Mustafa Yazici, Mehtap Demirkazik, Ismail Soner Koltas, Aytekin Cikman, Baris Gulhan, Tugce Duran, Aysun Yilmaz, Murat Kara Asian Pacific Journal of Tropical Medicine 2019 12(10):450-456 Objective: To investigate Blastocystis’ etiologic role and association with gastrointestinal symptomatology in acute and chronic urticaria patients and to identify Blastocystis subtypes responsible for urticaria. Methods: The study included urticaria patients and healthy individuals that presented to our polyclinic between June 2015 and May 2017. The participants were assigned into Group I (137 patients), subdivided into acute (72) and chronic urticaria patients (65), and Group Π (129 control individuals). Blastocystis presence was investigated by native-Lugol examination, trichrome staining, PCR using sequence tagged site primers, and DNA sequencing analysis. The phylogenetic tree was constructed. Results: The native-Lugol and trichrome staining methods revealed that 16 patients (16/133, 12.0%) had Blastocystis-positive stool samples, of which seven samples (7/133, 5.3%) belonged acute and nine (9/133, 6.8%) to chronic urticaria patients. Concerning Blastocystis subtypes, of the acute urticaria patients, three had subtype 1 (ST1), one had ST2, and three had ST3. Of the chronic urticaria patients, one had ST1 and eight had ST3. Blastocystis positivity was detected in two control individuals (2/123, 1.6%), both being ST3. All subtypes identified by PCR were confirmed by the sequencing analysis. The acute and chronic urticaria groups showed no statistically significant differences for Blastocystis positivity (P=0.60) and subtype distribution (P=0.15). A statistically significant difference was found between the urticaria patients and the controls for Blastocystis positivity (P<0.01), but not for subtype distribution (P=0.67) or for Blastocystis presence and gastrointestinal complaints. Conclusions: This study on Blastocystis subtype distribution among Turkish urticaria patients showed results consistent with the literature. It was concluded that Blastocystis should be kept in mind in patients with urticaria.

Detection of Trypanosoma spp. in Bandicota indica from the Thai-Myanmar border area, Mae Sot District Tak Province, Thailand Phuangphet Waree Molee, Natthiya Sakulsak, Somchai Saengamnatdej Asian Pacific Journal of Tropical Medicine 2019 12(10):457-462 Objective: To investigate the prevalence of trypanosome infection and their phylogeny in Bandicota indica rats from the cadmium-contaminated area of Mae Sot and the Myanmar border. Methods: Blood samples were taken from 100 animals, and parasite infection was examined by light microscopy observation and polymerase chain reaction (PCR) studies. Results: Trypanosoma spp. infection was found in 20% of the thin blood smear samples. PCR showed positive 623 bp DNA bands in 21 samples (21%). The sequencing analysis showed that all of the samples (100%) had the Trypanasoma lewisi 18S ribosomal RNA gene. Phylogenetic analysis confirmed that these 16 isolates of Trypanosoma spp. were closely related to Trypanasoma lewisi. Conclusions: Molecular detection using PCR is as effective as conventional light microscopy analysis. This study confirms that trypanosomal infection in rodents is still high; therefore, fleas as their vectors need to be controlled in order to prevent transmission to humans.

Prevalence and genetic divergence of Leptospira interrogans and Leptospira borgpetersenii in house rats (Rattus rattus) from Peninsular Malaysia Nurul Huda Mohamad Ikbal, Subha Bhassu, Khanom Simarani, Shigehiko Uni, Chew Chin Chan, Hasmahzaiti Omar Asian Pacific Journal of Tropical Medicine 2019 12(10):463-471 Objective: To evaluate the prevalence and divergence of genetically identified Leptospira spp. in the population of Rattus rattus. Methods: A total of 130 rats were used in this study. The infection within the rats were screened using polymerase chain reaction (PCR)-based diagnosis, with Leptospira genus-specific 16S rRNA primer and pathogenic Leptospira spp. specific LipL32 primer, on both kidney and liver tissues of Rattus rattus to detect the presence of potential Leptospira spp. Results: Out of 130 rats studied, 51 (39.23%) individuals were positive for leptospiral DNA. Basic Local Alignment Search Tool (BLAST) and phylogenetic analysis revealed that both pathogenic Leptospira interrogans and Leptospira borgpetersenii were predominantly identified. Phylogenetically, both genes disclosed similar clustering patterns of tree topologies between the two species. Although both genes were conserved, LipL32 gene portrayed higher nucleotide divergence (5.80%) compared to the 16S rRNA gene (0.60%). Minimum-spanning network displayed several haplotypes that are unique to each species, suggesting a higher degree of subdivision between both species. As for prevalence surveillance, both adult and subadult rats were susceptible to the infection, in which males were the most susceptible. Kidney was notable as the favourable organ for colonisation of leptospires. Rats captured from fresh markets were highly infected with Leptospira spp. (54.28%) compared to those from housing areas (26.47%). Conclusions: Rattus rattus represents an important asymptomatic transmitter of pathogenic leptospires, and hence is of public health concerns.

Comparative analysis of current diagnostic PCR assays in detecting pathogenic Leptospira isolates from environmental samples May-Ling Yap, Zamberi Sekawi, Hui-Yee Chee, Han Kiat Alan Ong, Vasantha Kumari Neela Asian Pacific Journal of Tropical Medicine 2019 12(10):472-478 Objective: To compare the efficiency of routine diagnostic PCR assays in detecting pathogenic Leptospira isolated from water and soils. Methods: Seven routine assays targeting six genes (lipL32, flaB, gyrB, lfb1, secY and ligB) were evaluated and compared on the cultures of two groups of pathogenic Leptospira from different sources. One group included 19 described reference strains recovered from infected human or animals, and another group included 22 environmental isolates from recreational and residential sites in Malaysia. The latter have been confirmed for presence of pathogenic Leptospira DNA. PCR positivity or detection sensitivity of each assay was determined and compared between the two groups. Results: Validation on reference strains showed 100.0% PCR sensitivity for all assays except ligB-PCR (95.0%) that failed to amplify Leptospira interrogans serovar Pomona. In marked contrast, there was a notable decline in sensitivity in the environmental isolates (lipL32-PCR, 95.5%;flaB-PCR, 90.9%; gyrB-PCR, 77.3%; lfb1-PCR, 59.1%; secY-PCRs, 40.9% G1/G2- PCR, 36.4%; ligB-PCR, 13.6%), implying a large genetic distance between the two groups, as well as nucleotide polymorphism among environmental isolates. Conclusions: High proportion of false-negative PCR results suggests a need of prudent selection of primers in detecting environmental pathogenic Leptospira. These findings offer valuable insights on the extensive biodiversity of genus Leptospira and its impact on the efficacy and development of molecular detection tool.

Non-related contact lens coinfection with Acanthamoeba and Fusarium Ranjit Sah, Meenu Chaudhary, Shusila Khadka, Rafael Toledo, Lucrecia Acosta Asian Pacific Journal of Tropical Medicine 2019 12(10):479-482 Rationale: Microbial keratitis caused by coinfection with more than one species of pathogens is a severe condition with an unfavorable prognosis. Patient concerns: An immunocompetent Nepali woman complained of pain in the left eye, redness, watering and decreased vision for 5 months. Interventions: The patient was discarded and accurately diagnosed with coinfection with Fusarium sp. and Acanthamoeba sp. The habit of washing the eyes with tap water from a domestic storage tank was the most likely source of infection since it was found to be contaminated with cysts of Acanthamoeba sp. The woman received eye drops of fluconazole and natamycin (5%), cefazoline (50 mg/mL), atropine, and tablets of itraconazole (100 mg), which were later switched to eye drops of clotrimazole (1%), natamycin (5%) and voriconazole (1%), and tablets of itraconazole. A full thickness penetrating keratoplasty was performed followed by treatment with eye drops of voriconazole (1%), natamet (5%), ofloxacin, atropine and carboxymethylcellulose for one week. Outcomes: After treatment, the condition of the patient significantly improved and was discharged one week after keratoplasty. Lessons: This is the first report of Acanthamoeba keratitis in Nepal and the first report of coinfection with Fusarium in this country and highlights the importance of early diagnosis of microbial keratitis both in single microorganism infections and coinfections, even in no contact lens wearers.