Comprehensive Genomic Analysis Identifies a Diverse Landscape of Sideroblastic and Nonsideroblastic Iron-Related Anemias with Novel and Pathogenic Variants in an Iron-Deficient Endemic Setting

Inherited iron metabolism defects are possibly missed or underdiagnosed in iron-deficient endemic settings because of a lack of awareness or a methodical screening approach. Hence, we systematically evaluated anemia cases (2019 to 2021) based on clinical phenotype, normal screening tests (high-performance liquid chromatography, α gene sequencing, erythrocyte sedimentation rate, C-reactive protein, and tissue transglutaminase), and abnormal iron profile by targeted next-generation sequencing (26-gene panel) supplemented with whole-exome sequencing, multiplex ligation probe amplification/mitochondrial DNA sequencing, and chromosomal microarray. Novel variants in ALAS2, STEAP3, and HSPA9 genes were functionally validated. A total of 290 anemia cases were screened, and 41 (14%) enrolled for genomic testing as per inclusion criteria. Comprehensive genomic testing revealed pathogenic variants in 23 of 41 cases (56%). Congenital sideroblastic anemia was the most common diagnosis (14/23; 61%), with pathogenic variations in ALAS2 (n = 6), SLC25A38 (n = 3), HSPA9 (n = 2) and HSCB, SLC19A2, and mitochondrial DNA deletion (n = 1 each). Nonsideroblastic iron defects included STEAP3-related microcytic anemia (2/23; 8.7%) and hypotransferrenemia (1/23; 4.3%). A total of 6 of 22 cases (27%) revealed a non-iron metabolism gene defect on whole-exome sequencing. Eleven novel variants (including variants of uncertain significance) were noted in 13 cases. Genotype-phenotype correlation revealed a significant association of frameshift/nonsense/splice variants with lower presentation age (0.8 months versus 9 years; P < 0.01) compared with missense variants. The systematic evaluation helped uncover an inherited iron defect in 41% (17/41) of cases, suggesting the need for active screening and awareness for these rare diseases in an iron-deficient endemic population.

The Challenge of Severe Acute Malnutrition in Inborn Errors of Metabolism: Does Medical Food Alone Suffice?

Glutaric aciduria type 1 (GA-1) is a treatable inborn error of metabolism caused by glutaryl-CoA dehydrogenase deficiency. This enzyme deficiency leads to accumulation of glutaric acid, 3-hydroxy glutaric acid, and glutaconic acid which are potentially neurotoxic. Patients with GA-1 have characteristic clinical and neuroimaging features that help us to clinch the diagnosis. Early diagnosis by newborn screening helps us to prevent the motor problems such as dystonia and spasticity. Treatment includes low-protein diet along with carnitine supplementation which may lead to deficiency of essential amino acids and hence malnutrition. Managing malnutrition in a child with inborn errors of metabolism (IEM) is challenging. Here, we describe a patient, a case of GA-1 on medical food, presenting with severe acute malnutrition, who improved with a combination of medical and home-made foods along with lysine-free, tryptophan-reduced amino acid supplements.

Comparative efficacy of early morning versus bedtime administration of levothyroxine in children with hypothyroidism: a prospective, open label, randomized, case-control study

INTRODUCTION

Studies in adults with hypothyroidism suggest an equal efficacy of bedtime versus early morning intake of levothyroxine. There is limited data on timing of levothyroxine administration in children.

MATERIAL AND METHODS

Children with hypothyroidism on early morning levothyroxine, and clinically and biochemically euthyroid, were assigned to receive levothyroxine at bedtime (group A) or were continued on early morning levothyroxine intake (group B). Clinical, anthropometric and laboratory evaluation (thyroid and lipid profiles, liver enzymes and creatinine) was done at baseline, and at 3 and 6 months.

RESULTS

Eighty-four children, 42 in each group, completed the study. The clinical and anthropometric parameters remained similar in the two groups at baseline and at 3- and 6-month follow-up visits. There was no difference in the mean serum concentrations of triiodothyronine, thyroxine and thyrotropin at the 3 time-points in the study. In addition, mean serum aspartate transaminase, alanine transaminase, creatinine and parameters of lipid profiles remained similar in the two groups. The requirement of levothyroxine was similar at baseline (48.6 ±16.9 µg vs. 49.6 ±19.5 µg, p-value 0.80) and at the endpoint (48.3 ±17.2 µg vs. 51.9 ±18.0 µg, p-value 0.46) in both groups. At the study end, 25 (60%) patients in group A and 17 (40%) in group B preferred bedtime dosing of levothyroxine.

CONCLUSIONS

We found an equal efficacy of bedtime intake compared to early morning intake of levothyroxine in maintaining an euthyroid state in children with hypothyroidism. Further studies are required to see if bedtime levothyroxine administration improves the quality of life of patients.

Patterns of geriatric anemia: A hospital-based observational study in North India

BACKGROUND

Geriatric anemia is a global health problem because of its high prevalence and associated significant morbidity and mortality.

AIM

The objectives of this study were to estimate the pattern of anemia in the elderly patients and the underlying etiology of anemia.

RESEARCH DESIGN AND METHODS

This was a hospital-based prospective observational study, conducted in patients aged 60 years and above at PGIMER, Chandigarh, a tertiary care center of North India. Anemia is defined as hemoglobin level less than 13 g/dl in men and 12 g/dl in women.

RESULTS

Among the 105 older patients with anemia, the mean value of hemoglobin was 8.8 ± 2.3 g/dl. The etiological distribution of anemia was iron deficiency in 26 patients (24.8%), chronic disease in 24 patients (22.9%), hematological disorders in 21 (20%), chronic kidney disease in 13 (12.4%), multifactorial in 8 (7.6%), vitamin B12 deficiency in 2 (1.9%), folate deficiency in 1 (0.9%), and hypothyroidism in 1 patient (0.9%). No etiology could be found in 9 patients (8.6%). 57.6% of the iron-deficient patients had upper gastrointestinal lesions and 30.7% had a nutritional cause. Common chronic diseases causing anemia were malignancy (36.6%) and liver disease (29.1%). The myelodysplastic syndrome was the commonest hematological disorder. 53.35% of the patients had normocytic anemia, 40% had microcytic anemia, and 6.6% had macrocytic anemia.

CONCLUSIONS

In most of the cases, anemia in the elderly had a treatable cause. Thus, a thorough investigation including gastrointestinal endoscopy is warranted. Unexplained progressive or unresponsive anemia requires bone marrow examination.

The deferiprone and deferasirox combination is efficacious in iron overloaded patients with β-thalassemia major: A prospective, single center, open-label study

BACKGROUND

The high cost, coupled with the need for continuous infusion, renders Desferrioxamine (DFO), a non-feasible option for iron-chelation in a large majority of patients with β-thalassemia major in developing countries. Monotherapy with deferiprone (DFP) or deferasirox (DFX) may not always attain optimal control, particularly in heavily iron-loaded patients. Combination of DFP and DFX is a potential alternative.

PROCEDURE

A prospective, single-center, open-label, uncontrolled study was conducted to evaluate the safety and efficacy of the combination in patients with β-thalassemia major. Patients who had received either DFP or DFX for >1 year and a serum ferritin >2,000 μg/L were enrolled. Blood counts, liver/renal functions, and serum ferritin were monitored during the 1-year study period. Facilities for cardiac T2*-MRI were unavailable.

RESULTS

Thirty-six patients with a mean age of 13 ± 6.9 years (range: 4-29) and a ferritin of 6,768 ± 4,145 μg/L formed the study cohort. Eight (22%) patients had transient gastrointestinal adverse effects. DFX was discontinued in one patient for persistent abdominal pain/diarrhea. Eight (22%) had joint symptoms; DFP was discontinued in two. Four (11%) patients had elevation in AST/ALT levels, managed with temporary interruption of DFX. Nine (25%) had an inconsistent elevation of creatinine to >33% of baseline; no intervention was done. One had transient proteinuria. None had neutropenia. At the end of 1 year, the serum ferritin reduced by a mean value of 3,275.3 ± 618.2 μg/L (P < 0.001).

CONCLUSIONS

The oral combination was found to be safe, efficacious, and a feasible option in patients with suboptimal response to monotherapy.

Risk factors for thromboembolism and pulmonary artery hypertension following splenectomy in children with hereditary spherocytosis

BACKGROUND

The aim was to study risk-factors for vascular thrombosis and incidence of pulmonary artery hypertension (PAH) in splenectomized children with hereditary spherocytosis (HS) at a single center.

PROCEDURE

Pre- and post-splenectomy hemoglobin and platelet counts were recorded. Post-splenectomy lipid-profile, fibrinogen, D-dimer, CRP and anti-coagulant-protein levels were compared to established controls. Echo-Doppler was performed for PAH.

RESULTS

Twenty-six children with HS had undergone splenectomy; the mean age at surgery was 7.9 ± 3.7 years. Nineteen of the 26 were prospectively investigated at a median duration of 4.5 years (range: 4 months to 19 years) following splenectomy. Thrombocytosis was observed in 19 (73%), whereas no patient had erythrocytosis at the last follow-up visit. Total cholesterol, LDL-C, HDL-C, and triglyceride levels were not deranged (P ≥ 0.3). Mean CRP levels (males: 2.8 ± 0.5; females: 2.1 ± 0.5 mg/L) were significantly higher than described for normal children (P < 0.001). Six (23%) patients had a positive D-dimer assay. Protein S, anti-thrombin-III and fibrinogen were in range. A single patient had a borderline low protein C activity. Lupus anticoagulant and anti-cardiolipin antibody assays were negative. The mean tricuspid regurgitant jet velocity (TRJV) was 1.8 ± 0.55 meter per second (range: 0-2.4). None had a TRJV ≥2.5 meter per second to suggest PAH.

CONCLUSIONS

There was no evidence of PAH, dyslipidemia, elevation of fibrinogen or a reduction in anti-coagulant proteins, at a median follow-up duration of 4.5 years following splenectomy in children with HS. However, elevated CRP level (42%), persistent thrombocytosis (73%) and elevated D-dimer levels (23%) were observed. These have been recognized as risk factors for cerebrovascular and coronary heart disease.

Vitamin D levels during and after resolution of ketoacidosis in children with new onset Type 1 diabetes

AIM

To study the effect of ketoacidosis on measured 25-hydroxyvitamin D3 in children with new onset Type 1 diabetes.

METHODS

Measurement of pH and bicarbonate levels was carried out in children with newly diagnosed Type 1 diabetes at presentation with ketoacidosis. 25-hydroxyvitamin D3 estimation was carried out at presentation (timepoint 1) and 1 month later (timepoint 2). There was no significant difference in the mean (±sd) 25-hydroxyvitamin D3 levels [35.39 (±25.79) vs 39.63 (±48.03) nmol/L; P = 0.661) at the two timepoints in the study.

RESULTS

Correlation analysis revealed a positive correlation between bicarbonate levels and timepoint 1, i.e. the lower the bicarbonate levels, the lower were the timepoint 1 levels and vice versa (correlation coefficient 0.538, P = 0.001). Timepoint 2 levels also showed a positive correlation with serum bicarbonate levels with a correlation coefficient of 0.379 (P = 0.032). None of the variables other than bicarbonate,.(age, gender, BMI, pH or time), was found to have the predictive ability for timepoint1 levels. Similarly for predicting timepoint 2 levels, BMI was found to have independent predictive ability in addition to bicarbonate.

CONCLUSIONS

Severe ketoacidosis, as judged by bicarbonate but not pH, may transiently lower 25-hydroxyvitamin D3 levels in children with new onset Type 1 diabetes. Persistence of low 25-hydroxyvitamin D3 levels after resolution of ketoacidosis suggests a state of permanent vitamin D deficiency in our patient population.