Longevity of serologic responses following a single dose of typhoid conjugate vaccine among children living with HIV in Pakistan: A prospective cohort study.

BACKGROUND: This study aimed to assess the longevity of serologic response and seroconversion rates at several time points following TCV vaccination among children living with HIV aged 6 months to 15 years in Pakistan. METHODS: From November 20, 2020, to January 2, 2021; 336 children were enrolled and followed up prospectively for 12 months. Blood samples were collected before the administration of TCV and at 4-6 weeks, 6 months, and 1 year after administration of a single dose (0.5 ml) of intramuscular Typbar TCV®. Samples were analyzed for anti-Vi-IgG antibodies using ELISA. Geometric mean titers (GMTs), seroconversion rates (fourfold rise in anti-Vi-IgG from baseline), and factors associated with sustained seroconversion at 1 year were evaluated using generalized linear mixed models. FINDINGS: The seroconversion rates were significantly lower in children aged 6 months to 5 years compared to children > 5 years; (127/216 (58·8%)) versus (81/111 (73·0%)) at 6 months and (110/217 (50·7%)) versus (78/109 (71·6%)) at 1 year, only two-third; 188/326 (57·7%) remained seroconverted at 1 year. The GMTs (95 % CI) were significantly lower in children aged 6 months to 5 years compared to children > 5 years, 9·6 (7·6, 12·0) versus 28·9 (20·2, 41·4) at 6 months, and 6·6 (5·4, 8·0) versus 23·1 (16·4, 32·5) at 1 year time point. The odds of sustained seroconversion significantly decreased with time (adjusted odds ratio (aOR): 0·232; 95 % CI: 0·136,0·396). The odds of sustained seroconversion following 1 year of TCV vaccination were significantly higher among children with non-severe HIV clinical disease (aOR: 10·6; 95 % CI: 1·5, 73·9) and children in elder age group (aOR: 7·45; 95 % CI: 11·2, 47·0). CONCLUSIONS: There was a decline in seroconversion after one year of TCV in children living with HIV. The decline was significant in children with severe or advanced HIV disease. A significant decrease in seroconversion rates was observed among children living with HIV following one year of TCV administration.

The spectrum of primary immunodeficiencies at a tertiary care hospital in Pakistan.

BACKGROUND: Primary Immunodeficiency Disorders (PIDs) are well-known disorders in the West. but the recognition and diagnosis of these disorders is challenging in developing countries. We present the spectrum of PIDs seen at a tertiary care center in Pakistan, identified using clinical case definitions and molecular methods. METHODS: A retrospective chart review of children suspected to have PID was conducted at the Aga Khan University Hospital (AKUH) Karachi, Pakistan from 2010 to 2016. Data on demographics, clinical features, family history of consanguinity, sibling death, details of laboratory workup done for PID and molecular tests targeted panel next generation sequencing (NGS) or whole exome sequencing (WES) performed at the Geha laboratory at Boston Children's Hospital, USA was collected. The study was exempted from the Ethical Review Committee of AKUH. RESULTS: A total of 43 children visited the hospital with suspected PID during the study period. Genetic testing was performed in 31/43 (72.1%) children. A confirmed diagnosis of PID was established in 20/43 (46.5%) children. A pathogenic gene variant was identified in 17(85%) of the 20 confirmed cases (Table 1). Twelve (60%) of the confirmed cases of PID were male. The most common presenting symptom was recurrent diarrhea 11/20 (55%). The mean (±S.D) age of the cases at the time of diagnosis was 4.2 (±4.1) years. Chronic granulomatous disease (CGD) was the most common 6/20 (30%) disorder, followed by severe combined immunodeficiency (SCID) 3/20 (15%), leukocyte adhesion deficiency (LAD) 3/20 (15%), agammaglobulinemia/hypogammaglobulinemia 3/20 (15%), and Hermansky-Pudlak Syndrome (HPS) 2/20 (10%). Wiskott-Aldrich Syndrome, Immunodeficiency Centromeric Instability and Facial Anomalies Syndrome (ICF 2), Trichohepatoenteric syndrome (TRES), and C3 deficiency were each diagnosed once {1/20 (4.3%) each} (Table 1). Of these 20 confirmed cases, almost all 19/20 (95%) had a family history of consanguinity. Sibling death was reported in 5/20 (25%) of these cases. Five out of the 20 (25%) children died over the 7-year period for various reasons. CONCLUSION: PIDs are not uncommon in Pakistan; their diagnosis may be missed or delayed due to the overlapping of clinical features of PID with other diseases and a lack of diagnostic facilities. There is a need to build capacity for early recognition and diagnosis of PIDs to decrease morbidity and mortality.

Clinical profile and outcome of antibiotic lock therapy for bloodstream infections in pediatric hematology/oncology patients in a tertiary care hospital, Karachi, Pakistan.

BACKGROUND: Intravascular catheters are susceptible to infections, thus requiring catheter removal and leading to increased morbidity and costs. Antibiotic lock therapy (ALT) is a therapeutic technique that is used to salvage the catheter. The aim of this study was to evaluate the outcome of antibiotic lock therapy in bloodstream infections in pediatric hematology/oncology patients in a tertiary care hospital, Karachi. METHODS: A retrospective review was performed from January 2013 to December 2017 of pediatric hematology/oncology patients with bloodstream infections and who received ALT at Aga Khan University Hospital. All cases of polymicrobial infections, catheter removal, or malfunction before the completion of ALT were excluded. Descriptive analysis was carried out using SPSS version 20. RESULTS: A total of nine hematology/oncology patients were eligible. The catheter was salvaged in 7/9 (77.8%) children, and in 2/9 (22.2%) cases, catheter was removed because of persistent bacteremia. The most common organism isolated was Staphylococcus non-aureus species (33.3%). Relapse with a similar pathogen occurred in 2 (22.2%) patients and 2 (22.2%) of them developed an exit-site infection. CONCLUSION: In our experience, in almost two thirds of the cases, the catheter was salvaged, but disappointingly, relapses were high when the infection was due to Staphylococcus spp. Although this is a small study, our results show that ALT can be a potential safe adjunctive strategy to treat catheter-related bloodstream infections (CRBSI). However, we need larger prospective studies to test the safety and efficacy of ALT to develop specific ALT recommendations and guidelines particularly in children.

Outcome of inadvertent high dose BCG administration in newborns at a tertiary care hospital, Karachi- Case series.

Bacillus Calmette-Guérin (BCG) vaccine is given to newborns soon after birth. BCG vaccine overdose has been rarely reported. Here we report the outcome of newborns who accidently received high dose BCG at a tertiary care hospital, Karachi. We reviewed records of 26 newborns, who accidentally received intradermal high dose BCG, used for the treatment of urinary bladder cancers and 80 times higher dose than the BCG used for routine vaccination. The incident happened from 14-16th April, 2016 at Aga Khan University Hospital, Karachi. Analysis was carried out using SPSS. A total of 23/26(88.5%) newborns were followed for atleast 3 months and 11/26 (42.3%) were followed for atleast one year. 13/26 (50%) were male. All 26 patients were prescribed isoniazid and rifampicin for 3 months. 3/26 (11.5%) were lost to follow-up before completion of anti-tuberculous drugs (ATT). Lesions at the BCG site were observed in 16/26 (61.5%) infants, of which 15 (93.8%) had a papule, 3 (18.8%) developed a pustule, 3 (18.8%) had skin induration and 2 (12.5%) had skin erythema. Axillary lymphadenopathy was observed in 1/26 (3.8%) patient. Coagulation was deranged in 3/26 (11.5%) of babies. Intracranial bleeding was observed in 1/26 (3.8%) case. Localized skin lesions were the most common adverse events. None of them developed clinical tuberculosis. Chemoprophylaxis for inadvertent high dose BCG administration should be given for atleast 3 months. Furthermore, vigilant follow-up, transparency and disclosure are the vital steps in the management of any medical error.

Large mediastinal mass in a 15-year-old boy.

Hyperimmunoglobulin E syndrome is a rare multisystem inherited disorder characterised by high serum IgE levels, skin disorder causing eczema, dermatitis, recurrent staphylococcal infections and pulmonary infections and various skeletal and connective tissue abnormalities. Common presentation is with recurrent skin and sinopulmonary infections. Several features unrelated to immune system such as characteristic facial features, hyperextensibility of joints, multiple bone fractures and craniosynostosis have been described in the literature. We describe a rare presentation of this disease with invasive aspergillosis presenting as mediastinal mass with extension to mediastinal structures and pulmonary vasculature.

Clinical manifestations and treatment outcomes in HIV-1-infected children receiving antiretroviral therapy in Karachi, Pakistan.

INTRODUCTION: The impact of antiretroviral (ARV) therapy on immunological and growth parameters in HIV-positive children in Pakistan has not been reported to date. METHODOLOGY: A retrospective chart review of children diagnosed with HIV at the Sindh AIDS Control Proigramme (SACP) and registered at the Aga Khan University, Karachi, between January 2005 and 2013 was conducted, evaluating clinical and laboratory profiles of HIV+ ARV+ children for ARV impact (serial height and weight CD4 and viral counts). RESULTS: Twenty-four children were diagnosed and registered as HIV positive over five years, and 20 were started on ARV. Six were excluded from analysis (ARV duration < 6 months). Nine (64.3%) of 14 fulfilled WHO criteria for treatment failure at a median duration of 25 weeks (IQR 18-32) on ARV and underwent resistance genotyping. All nine had NNRTI resistance, two had high-grade NRTI resistance (≥ 4 thymidine analog mutations). Median age at start of ARV was 71.5 weeks (IQR 37.5-119). Median baseline weight for age (WAZ) and height for age (HAZ) z-scores changed from -1.94 to 1.69 and -1.99 to -1.59, respectively, after six months of therapy. Median CD4 percentage and viral load at baseline changed from 13.8 to 17.8, while viral load changed from 285 × 104 copies to zero at six months. CONCLUSIONS: ARV improved absolute CD4 and viral counts. Weight and height did not  improve significantly, highlighting the need for aggressive nutritional rehabilitation. Early development of ARV resistance in these children requires formal assessment.

Risk factors for complicated varicella infection in pediatric oncology patients at a tertiary health care facility in Pakistan.

INTRODUCTION: Varicella zoster infection (VZI) is well recognized as a potential cause of morbidity and mortality in immunocompromised pediatric oncology patients (POP). The purpose of this study was to describe the clinical profile and risk factors for complications and outcomes of VZI in POP treated with acyclovir. METHODOLOGY: Medical records of all POP with a discharge diagnosis of VZI over a period of seven years (2005-2011) were reviewed. The demographic features, underlying malignancy, risk factors for VZI, complications, and outcomes were recorded. RESULTS: Thirty-six POP with VZI were identified. Leukemia was the most common underlying malignancy (n = 20, 58.8%), followed by lymphoma (n = 7, 20.6%) and solid organ tumors (n = 7, 20.6%). Most of the cases (41%) were observed in children under five. All patients were treated with acyclovir. Varicella-related complications developed in 10 (29%) patients. The most frequent complication was bloodstream infection (n = 3, 8.8%), followed by pneumonia (n = 2, 5.9%), skin infection (n = 2, 5.9%), hepatitis, renal failure, and encephalitis. Independent risk factors associated with complications were age < five years, weight for age < fifth percentile, delay in seeking care (> seven days after onset of symptoms) and severe neutropenia (ANC < 500/cm). One child died secondary to varicella encephalitis. CONCLUSION: Our data suggests that young age, poor health-seeking behavior, severe neutropenia, and being underweight are the major risk factors for the development of varicella-related complications in POP in developing countries. These complications could be favorably modified through active immunization of immunocompetent children.

Antibiotic resistance-the need for global solutions.

The causes of antibiotic resistance are complex and include human behaviour at many levels of society; the consequences affect everybody in the world. Similarities with climate change are evident. Many efforts have been made to describe the many different facets of antibiotic resistance and the interventions needed to meet the challenge. However, coordinated action is largely absent, especially at the political level, both nationally and internationally. Antibiotics paved the way for unprecedented medical and societal developments, and are today indispensible in all health systems. Achievements in modern medicine, such as major surgery, organ transplantation, treatment of preterm babies, and cancer chemotherapy, which we today take for granted, would not be possible without access to effective treatment for bacterial infections. Within just a few years, we might be faced with dire setbacks, medically, socially, and economically, unless real and unprecedented global coordinated actions are immediately taken. Here, we describe the global situation of antibiotic resistance, its major causes and consequences, and identify key areas in which action is urgently needed.