Supraventricular tachycardia associated with severe diabetic ketoacidosis in a child with new-onset type 1 diabetes mellitus.

Diabetic ketoacidosis is one of the most serious and common complications of diabetes, with between 15 and 70% of new-onset type 1 diabetes mellitus worldwide presented with diabetic ketoacidosis. Supraventricular tachycardia, however, is an infrequent complication of diabetic ketoacidosis. We present the case of a child with a new-onset type 1 diabetes mellitus with supraventricular tachycardia as a complication of paediatric diabetic ketoacidosis. The patient received intravenous fluid resuscitation, insulin, and potassium supplementation and subsequently developed stable supraventricular tachycardia initially, confirmed on a 12-lead electrocardiogram despite a structurally normal heart and normal electrolytes. Vagal manoeuvers failed to achieve sinus rhythm. The patient went into respiratory distress and was intubated, for mechanical ventilation. She received one dose of adenosine with successful conversion to sinus rhythm and a heart rate decreased from 200 to 140 beats per minutes. We conclude that supraventricular tachycardia can occur as a complication of diabetic ketoacidosis, including in new-onset type 1 diabetes mellitus. Furthermore, a combination of acidosis, potassium derangement, falling magnesium, and phosphate levels may have precipitated the event. Here, we report a case of supraventricular tachycardia as a complication of paediatric diabetic ketoacidosis.

Clinical profile and mutation spectrum of long QT syndrome in Saudi Arabia: The impact of consanguinity.

BACKGROUND: Congenital long QT syndrome (LQTS) is an inherited, potentially fatal arrhythmogenic disorder. At least 16 genes have been implicated in LQTS; the yield of genetic analysis of 3 genes (KCNQ1, KCNH2, and SCN5A) is about 70%, with KCNQ1 mutations accounting for ∼50% of positive cases. LQTS is mostly inherited in an autosomal dominant pattern. Systemic analysis of LQTS has not been previously conducted in a population with a high degree of consanguinity. OBJECTIVES: To describe the clinical and molecular profiles of LQTS in the highly consanguineous Saudi population. METHODS: Fifty-six Saudi families with LQTS were consecutively recruited and evaluated. Sequencing of KCNQ1, KCNH2, and SCN5A genes was conducted on all probands, followed by screening of family relatives. RESULTS: Genetic analysis was positive in 32 (57.2%) families, with mutations in KCNQ1 identified in 28 families (50%). Surprisingly, 17 (53.1%) probands were segregating homozygous mutations. Family screening identified 123 individuals with mutations; 89 (72.4%) were heterozygous, 23 (18.7%) were homozygous, and 11 (8.9%) were compound heterozygous. Compared to heterozygous, the phenotype was more severe in homozygous individuals, with cardiac symptoms in 78.3% (vs 12.4%), family history of sudden death in 64.7% (vs 44.4%), and prolonged QT interval in 100% (vs 43.8%). Congenital deafness was found in 11 (47.8%) homozygous probands. CONCLUSION: Our study provides insight into the clinical and molecular profiles of LQTS in a consanguineous population. It underscores the importance of preemptive management in homozygous patients with LQTS and the value of clinical and molecular screening of at-risk relatives.

A Novel Mutation in the CYP11B1 Gene Causes Steroid 11ß-Hydroxylase Deficient Congenital Adrenal Hyperplasia with Reversible Cardiomyopathy.

Congenital adrenal hyperplasia (CAH) due to steroid 11ß-hydroxylase deficiency is the second most common form of CAH, resulting from a mutation in the CYP11B1 gene. Steroid 11ß-hydroxylase deficiency results in excessive mineralcorticoids and androgen production leading to hypertension, precocious puberty with acne, enlarged penis, and hyperpigmentation of scrotum of genetically male infants. In the present study, we reported 3 male cases from a Saudi family who presented with penile enlargement, progressive darkness of skin, hypertension, and cardiomyopathy. The elder patient died due to heart failure and his younger brothers were treated with hydrocortisone and antihypertensive medications. Six months following treatment, cardiomyopathy disappeared with normal blood pressure and improvement in the skin pigmentation. The underlying molecular defect was investigated by PCR-sequencing analysis of all coding exons and intron-exon boundary of the CYP11B1 gene. A novel biallelic mutation c.780 G>A in exon 4 of the CYP11B1 gene was found in the patients. The mutation created a premature stop codon at amino acid 260 (p.W260 (∗) ), resulting in a truncated protein devoid of 11ß-hydroxylase activity. Interestingly, a somatic mutation at the same codon (c.779 G>A, p.W260 (∗) ) was reported in a patient with papillary thyroid cancer (COSMIC database). In conclusion, we have identified a novel nonsense mutation in the CYP11B1 gene that causes classic steroid 11ß-hydroxylase deficient CAH. Cardiomyopathy and cardiac failure can be reversed by early diagnosis and treatment.