Pediatric Kidney Biopsies in Oman: A Retrospective Study.

Objectives: To determine the spectrum of kidney diseases in Omani children < 13 years of age and to evaluate the complications following kidney biopsy. Methods: This study retrospectively investigated the hospital data of children who underwent kidney biopsies from January 2014 to June 2019 at Royal Hospital, Muscat, Oman. Results: The subjects comprised of 78 children with a median age of 8.0 years (range = 0-13 years). Histopathology showed minimal change disease in 15 (19.2%) children, lupus nephritis in 13 (16.7%), and focal segmental glomerulosclerosis in 13 (16.7%). The most common post-biopsy complications were pain that required analgesia (38; 49.4%) followed by gross hematuria (10; 13.0%). No patient required blood transfusion or surgical intervention. Conclusions: Minimal change disease was the most common histopathological finding in this cohort of Omani children. The records did not mention any major complications following the renal biopsy procedure.

Genetic analysis and outcomes of Omani children with steroid-resistant nephrotic syndrome.

BACKGROUND: Nephrotic syndrome (NS) is one of the most common kidney disorders seen by pediatric nephrologists and is defined by the presence of heavy proteinuria (>3.5 g/24 h), hypoalbuminemia (<3.5 g/dL), edema, and hyperlipidemia. Most children with NS are steroid-responsive and have a good prognosis following treatment with prednisolone. However, 10%-20% of them have steroid-resistant nephrotic syndrome (SRNS) and fail to respond to treatment. A significant proportion of these children progress to kidney failure. METHODS: This retrospective study aimed to determine the underlying genetic causes of SRNS among Omani children below 13 years old, over a 15-year period and included 77 children from 50 different families. We used targeted Sanger sequencing combined with next-generation sequencing approaches to perform molecular diagnostics. RESULTS: We found a high rate of underlying genetic causes of SRNS in 61 (79.2%) children with pathogenic variants in the associated genes. Most of these genetically solved SRNS patients were born to consanguineous parents and variants were in the homozygous state. Pathogenic variants in NPHS2 were the most common cause of SRNS in our study seen in 37 (48.05%) cases. Pathogenic variants in NPHS1 were also seen in 16 cases, especially in infants with congenital nephrotic syndrome (CNS). Other genetic causes identified included pathogenic variants in LAMB2, PLCE1, MYO1E, and NUP93. CONCLUSION: NPHS2 and NPHS1 genetic variants were the most common inherited causes of SRNS in Omani children. However, patients with variants in several other SRNS causative genes were also identified. We recommend screening for all genes responsible for SRNS in all children who present with this phenotype, which will assist in clinical management decisions and genetic counseling for the affected families.

Epidemiology, Management, and Outcome of Atypical Hemolytic Uremic Syndrome in an Omani Cohort.

Objectives: Atypical hemolytic uremic syndrome (aHUS) is a rare, life-threatening disease of chronic uncontrolled complement pathway activation that leads to thrombotic-microangiopathy, along with severe organ damage, including end-stage kidney disease. This study aimed to evaluate the epidemiology, management, and outcome of aHUS in an Omani population. Methods: This retrospective descriptive cohort study assessed all cases of aHUS diagnosed and followed up at two tertiary care centers in Oman from January 2008 to December 2019, based on clinical features, complement pathway assays, histopathological, and genetic testing. Results: The study accrued 19 patients who fulfilled the inclusion criteria, of whom 11 (57.9%) were male. The participants' median age was 25.0 years (range = 0.1-69.0). Most (15; 78.9%) patients presented in the acute phase of the disease. The triad of hemolytic anemia, acute kidney injury, and thrombocytopenia was present in all patients. A trigger factor (e.g., infection) was identified in 68.4% of cases. Of the 14 (73.7%) patients who underwent kidney biopsy, 10 (71.4%) were found to have aHUS in native kidneys and three in grafted kidneys. Of the 11 (57.9%) patients who underwent genetic analysis, five (45.5%) were found to have a known pathogenic variant in their aHUS susceptibility genes. Plasma exchange followed by eculizumab was the treatment method in 11 (57.9%) cases. Complete renal recovery was achieved in seven (36.8%) patients, while four (21.1%) passed away during the study period. Conclusions: The wide spectrum and multiple expressions of aHUS make it a challenge to diagnose and consequently may delay the commencement of the targeted treatment. Eculizumab is considered the first-line therapy and should be commenced as early as possible.

Awareness and Attitude Towards the Premarital Screening Programme Among High School Students in Muscat, Oman.

OBJECTIVES: This study aimed to explore high school students' awareness and attitude towards premarital screening (PMS). METHODS: This cross-sectional study was conducted in 10 public high schools in Muscat, Oman from May to July 2016. A three-part self-administered questionnaire was used to collect data from grade 12 students. The first part focused on respondents' sociodemographic characteristics, while the second part dealt with awareness of the national PMS programme and the third part explored attitudes towards the national PMS programme. RESULTS: A total of 1,541 participants (response rate: 91.1%) completed the questionnaire. Most participants (78.1%) were aware of the availability of the PMS programme and their main source of information was family and friends (34.3%). The majority of students (87.4%) believed that PMS is important and most students (87.2%) indicated that they would undergo PMS. Over half of the students (55.3%) agreed that PMS should be mandatory before marriage and approximately one-third (38.3%) were in favour of having laws and regulations to prevent consanguineous marriages. Females were significantly more in favour of making PMS mandatory (P = 0.002) and enforcing PMS laws (P = 0.010) compared to males. CONCLUSION: Most respondents had good levels of knowledge about the PMS programme and half thought it is important to be tested. However, some students were not in favour of PMS. Increasing awareness about Oman's PMS programme is important and motivating students could contribute significantly to increasing the utilisation of the PMS programme and to limiting genetic blood disorders.

Pediatric Renal Transplantation in Oman: A Single-center Experience.

OBJECTIVES: This study sought to report 22 years experience in pediatric kidney transplantation in Oman. METHODS: Electronic charts of all Omani children below 13 years of age who received a kidney transplant from January 1994 to December 2015 were reviewed. Data collected included patient demographics, etiology of end-stage kidney disease, modality and duration of dialysis, donor type, complication of kidney transplantation (including surgical complications, infections, graft rejection) graft and patient survival, and duration of follow-up. RESULTS: During the study period transplantation from 27 living related donors (LRDs), 42 living unrelated donors (LURDs), also referred to as commercial transplant, and one deceased donor were performed. The median age at transplantation was nine years for both groups. The most common primary diagnosis was congenital anomalies of the kidney and urinary tract in 32.8% of patients followed by familial nephrotic syndrome in 20.0% and polycystic kidney disease in 18.5%. Almost half the patients were on hemodialysis before transplantation, 35.7% were on peritoneal dialysis, and 14.2% received preemptive renal transplantation. Children who received LURD kidneys had high surgical complications (42.8%) compared to the LRDs group (17.8%). Five patients from LURDs group had early graft nephrectomy and four patients developed non-graft function or delayed graft function. In addition, patients in the LURDs group had a higher incidence of hypertension and acute rejection. Graft and patient survival were both better in the LRDs than the LURDs group. CONCLUSIONS: Although our pediatric kidney transplant program is a young program it has had successful patient outcomes comparable to international programs. Our study provides evidence that in addition to legal and ethical issues with commercial transplant, it also carries significantly higher morbidity and reduced graft and patient survival.

Primary hyperoxaluria type 1 in 18 children: genotyping and outcome.

Background. Primary hyperoxaluria belongs to a group of rare metabolic disorders with autosomal recessive inheritance. It results from genetic mutations of the AGXT gene, which is more common due to higher consanguinity rates in the developing countries. Clinical features at presentation are heterogeneous even in children from the same family; this study was conducted to determine the clinical characteristics, type of AGXT mutation, and outcome in children diagnosed with PH1 at a tertiary referral center in Oman. Method. Retrospective review of children diagnosed with PH1 at a tertiary hospital in Oman from 2000 to 2013. Result. Total of 18 children were identified. Females composed 61% of the children with median presentation age of 7 months. Severe renal failure was initial presentation in 39% and 22% presented with nephrocalcinosis and/or renal calculi. Family screening diagnosed 39% of patients. Fifty percent of the children underwent hemodialysis. 28% of children underwent organ transplantation. The most common mutation found in Omani children was c.33-34insC mutation in the AGXT gene. Conclusion. Due to consanguinity, PH1 is a common cause of ESRD in Omani children. Genetic testing is recommended to help in family counseling and helps in decreasing the incidence and disease burden; it also could be utilized for premarital screening.