Background. Mycobacterium tuberculosis (M. tuberculosis) that causes tuberculosis (TB) kills millions of infected people annually especially multidrug-resistant tuberculosis (MDR-TB). On infection, macrophages recognize the mycobacteria by toll-like receptor (TLR) followed by phagocytosis and control of mycobacteria. In addition, macrophages also secrete IL-12 to induce IFN-γ production by T, which, in turn, increases the phagocytosis and oxidative burst. Individuals with defects in innate or adaptive immunity exhibit increased susceptibility to M. tuberculosis. Understanding these immunologic mechanisms will help in TB control. We aimed to investigate the immunopathologic mechanisms in MDR-TB and role of recombinant human interferon-gamma (rhIFN-γ). Study Design and Methods. Monocyte-derived macrophages (MDMs) were generated from peripheral blood mononuclear cells of MDR-TB patients and healthy subjects and were investigated for immunologic response by ELISA and flow cytometry. Results. Different functional and molecular anomalies were observed in macrophages. In addition, a defective immune response to M. tuberculosis from the patient’s MDMs was characterized, which in turn improved by pretreatment with rhIFN-γ. Conclusion. This work highlights the fact that rhIFN-γ improves macrophages function against M. tuberculosis and treatment of patients with poor responsiveness to TB therapy may be needed in future to include IFN-γ as adjuvant therapy after the full characterization of pathological and molecular mechanisms in these and in other more multidrug-resistant TB patients.

Background: Distribution of Hepatitis C Virus (HCV) genotypes may be changed over time. Epidemiological Studies on distribution patterns of HCV genotypes in Pakistani population might assist for better treatment options and preventive strategies. Objectives: This study was conducted to determine distribution patterns of HCV genotypes in different geographical regions of Pakistan. Patients and Methods: In this cross-sectional study, 1818 randomly selected patients from different geographical regions of Pakistan, diagnosed with HCV infection by the third generation Enzyme Linked Immunosorbent Assay (ELISA), were included between April 2011 and December 2013. HCV RNA was detected in serum samples of patients by Reverse Transcription Polymerase Chain Reaction (RT- PCR) of the core region. Qualitative PCR was performed to determine viral load. HCV genotyping was performed by RT-nested PCR using type-specific primers of the core region. Frequency of different genotypes among patients was assessed according to gender, age and geographical region at the time of sampling. Results: Of 1818 HCV RNA positive samples, HCV genotypes PCR fragments were detected in 1552 (85.5%) samples. HCV genotype 3a was the predominant genotype (39.4%) followed by genotype 2a (24.93%). HCV genotype 3 was the predominant genotype in Punjab and Sindh regions, while genotype 2 was the most predominant genotype in Khyber Pakhtunkhwa region and the second predominant genotype after genotype 3 in Sindh region. The incidence of genotype 2a is increasing in our country with decrease in the incidence of genotype 3a. A higher incidence of HCV various genotypes were observed among male patients and those younger than 45 years. Conclusions: This study may facilitate treatment options and preventive strategies in Pakistan. Keywords: HCV Genotypes; Distribution Patterns; Geographical Regions; Pakistan

Autosomal recessive anophthalmia and microphthalmia are rare developmental eye defects occurring during early fetal development. Syndromic and non-syndromic forms of anophthalmia and microphthalmia demonstrate extensive genetic and allelic heterogeneity. To date, disease mutations have been identified in 29 causative genes associated with anophthalmia and microphthalmia, with autosomal dominant, autosomal recessive and X-linked inheritance patterns described. Biallelic ALDH1A3 gene variants are the leading genetic causes of autosomal recessive anophthalmia and microphthalmia in countries with frequent parental consanguinity. This study describes genetic investigations in two consanguineous Pakistani families with a total of seven affected individuals with bilateral non-syndromic clinical anophthalmia. Using whole exome and Sanger sequencing, we identified two novel homozygous ALDH1A3 sequence variants as likely responsible for the condition in each family; missense mutation [NM_000693.3:c.1240G > C, p.Gly414Arg; Chr15:101447332G > C (GRCh37)] in exon 11 (family 1), and, a frameshift mutation [NM_000693.3:c.172dup, p.Glu58Glyfs*5; Chr15:101425544dup (GRCh37)] in exon 2 predicted to result in protein truncation (family 2). This study expands the molecular spectrum of pathogenic ALDH1A3 variants associated with anophthalmia and microphthalmia, and provides further insight of the key role of the ALDH1A3 in human eye development.

Background: Retinitis pigmentosa (RP) is the most common inherited retinal dystrophy, affecting approximately 1 in 4000 individuals worldwide. The most common form of syndromic RP is Usher syndrome (USH) accounting for approximately 20–30 % of RP cases. Mutations in the USH2A gene cause a significant proportion of recessive non-syndromic RP and USH type II (USH2). This study aimed to determine the causative role of the USH2A gene in autosomal recessive inherited ocular diseases and to establish genotype-phenotype correlation associated with USH2A variants. Methods: We performed direct Sanger sequencing and co-segregation analysis of the USH2A gene to identify disease causing variants in a non-syndromic RP family, two USH2 families and two Keratoconus (KC) families. Results: Disease causing variants in the USH2A gene were identified in two families displayed KC and USH2 phenotypes. A novel variant c.4029T > G, p.Asn1343Lys in the USH2A gene was detected in a Pakistani family with KC phenotype. In addition, a missense variant (c.7334 C > T, p. Ser2445Phe) in the USH2A gene was found segregating in another Pakistani family with USH2 phenotype. Homozygosity of identified missense USH2A variants was found associated with autosomal recessive inherited KC and USH2 phenotypes in investigated families. These variants were not detected in ethnically matched healthy controls. Moreover, the USH2A variants were predicted to be deleterious or potentially disease causing by PolyPhen-2, PROVEAN and SIFT. Conclusions: This study provided first evidence for association of a novel USH2A variant with KC phenotype in a Pakistani family as well as established the phenotype-genotype correlation of a USH2A variant (c.7334 C > T, p. Ser2445Phe) with USH2 phenotype in another Pakistani family. The phenotype-genotype correlations established in present study may improve clinical diagnosis of affected individuals for better management and counseling.

Objective: Studies on diabetic foot ulcers (DFU) involving a representative sample of patients in Pakistan are scarce. This study aimed to determine baseline characteristics of infected DFUs in patients hospitalised at the Pakistan Institute of Medical Sciences Islamabad. Method: In this cross-sectional study, carried out during May 2015 and June 2016, foot ulcer characteristics of patients with DFUs were investigated and documented. From infected DFUs, aerobic bacterial pathogens were isolated, identified and evaluated for antimicrobial susceptibility. Results: A total of 214 patients were recruited to the study, 62.6% of which were male, 90.2% were aged ≥40 years, 76.2% had type 1 diabetes and 78.5% had poor glycaemic control at time of presentation to hospital. Most patients had grade 3/moderate ulceration (based on the Wagner and International Working Group on the Diabetic Foot/Infectious Diseases Society of America criteria). Over half of the DFUs (57.9%) were of ≤3 months' duration and 70.1% were ≥3 cm². Of the patients with deep infection grade ulcers, 26.6% underwent amputation, accounting for their prolonged hospital stay (≥20 days). Significant differences were observed between patients with type 1 and type 2 diabetes with DFUs in relation to gender (p≤0.0001), ulcer size (p=0.0421) and duration of hospital stay (p=0.0253). The most significant predictors for lower extremity amputation were osteomyelitis (p=0.0114), retinopathy (p=0.0001) and neuropathy (p=0.0001. Piperacillin/tazobactam was found to be an effective antibiotic against the most commonly isolated Staphylococcus non-aureus (35.48%), Pseudomonas aeruginosa (22.26%), and Staphylococcus aureus (20.96%) species indentified in the DFU infections. Conclusion: The findings of this study may be helpful in the optimal management and appropriate treatment of patients with infected DFUs.

In the current study, the possible outcome of gender difference and genotypic polymorphism of the ABCB1 gene encoding P-glycoprotein on the pharmacokinetics of azithromycin has been evaluated. An open-label, comparative pharmacokinetic study was done in healthy Pakistani volunteers (females (n = 8) and males (n = 8)). They were administered a single 500 mg oral dose of azithromycin. Blood samples (≈5 mL) were collected in heparinized tubes and the HPLC/MS/MS method was used to determine azithromycin plasma levels. ABCB1 polymorphism (single nucleotide polymorphisms) at C3435T, G26SST was performed using the RFLP–PCR method. The Student t test was applied to compare pharmacokinetic parameters of azithromycin between male and female human subjects (at 95% CI) using GraphPad Prism-8. A significant difference was observed in pharmacokinetic parameters between males and females, as C_max in males (230 ± 80.2 ng/mL) was significantly higher than in females (224.9 ± 75.5 ng/mL), while [ ] was also significantly higher (p < 0.05) in males (2102 ± 200.3 ng·h⁻¹·mL⁻¹) compared to females (1825.7 ± 225.4 ng·h⁻¹·mL^–1). There was a significant variation in C_max and AUC in three ABCB1 genotyping groups as well. Gender difference and ABCB1 gene polymorphisms have a significant impact on the pharmacokinetics of azithromycin, as they contribute to interindividual variability in therapeutic response.