ABSTRACT
BACKGROUND: Reference values for right ventricular dimension and systolic function in Nigerian children are scarce despite their high burden of right ventricular abnormalities. Reference values from other countries may not be suitable for use in Nigerian children because of possible racial variations in cardiac size. PURPOSE: To develop reference values for right ventricular dimension and systolic function in healthy Nigerian children aged 5-12 years. METHODS: This descriptive cross-sectional study conducted between July and November 2019 included 480 healthy boys and girls aged 5-12 years. The participants were randomly selected from 6 primary schools in the Ikeja Local Government area of Lagos State and their weights and heights measured. Body mass index and body surface area were calculated. Echocardiography was performed at rest in the left lateral position. RESULTS: The right ventricular end-diastolic basal diameter (RVD1), right ventricular end-diastolic mid-cavity diameter (RVD2), and right ventricular end-diastolic length (RVD3) were obtained. The right ventricular end-diastolic basal diameter (RVD1), right ventricular end-diastolic mid-cavity diameter (RVD2), and right ventricular end-diastolic length (RVD3) were obtained, as well as tricuspid annular plane systolic excursion (TAPSE) and tissue Doppler-derived right ventricular systolic excursion velocity (S'). The overall mean±standard deviation (SD) values for RVD1, RVD2, RVD3, TAPSE, and S' were 32.95±4.2, 25.86±3.5, 54.57±7.5, 20.11±2.3, and 18.24±2.2, respectively. Age- and sex-specific mean and SD values of the same cardiac indices were determined. Z score charts and the mean± 2SD right ventricular dimensions and systolic function were generated. All right ventricular dimensions were positively correlated with weight, height, body surface area, and body mass index. Only height correlated consistently with TAPSE and S'. CONCLUSION: The observed mean right ventricular dimension indices differed from those derived elsewhere, suggesting that values from other countries may be inappropriate for Nigerian children. These reference values are applicable in daily clinical practice.
ABSTRACT
BACKGROUND: Correction of vitamin D deficiency through administration of either vitamin D2 or D3 has been shown to reduce chronic bone pains and frequency of acute bone pains, increase bone density as well as improve growth stature in children with sickle cell anemia (SCA). Findings vary on the effectiveness of the two forms of the vitamin. The current study was carried out to compare the effectiveness of a 6-week treatment course of vitamin D2 and D3 in the correction of hypovitaminosis D (vitamin D insufficiency and deficiency) as well as evaluate treatment response to derangement of serum calcium and alkaline phosphatase (ALP) in children with SCA in steady state. METHODS: The study was a randomized, double-blind clinical trial of 174 children with SCA aged 1 - 18 years. Subjects with hypovitaminosis D (baseline serum 25-hydroxyvitamin D (25(OH)D) below 75 nmol/L) were randomized into two treatment arms. Each arm treated either of the two forms of vitamin D had a once weekly dose of 50,000 IU for a period of 6 weeks. RESULTS: Median rise in serum 25(OH)D after 6 weeks of oral vitamin D2 or D3 was similar between the two groups (median rise in 25(OH)D of 17.8 nmol/L in D2, 15.3 nmol/L in D3 groups). Also, there was no significant difference in the proportion of subjects that improved in their vitamin D status in both treatment arms (P = 0.409). Treatment was significantly associated with increase in proportion of subjects with normal serum calcium (P ≤ 0.001) and decrease in proportion of subjects with elevated serum ALP (P ≤ 0.001). CONCLUSION: Once weekly dose (50,000 IU) of either vitamin D supplement has equal effectiveness in correction of hypovitaminosis D. However, vitamin D3 may be cost-effective because it is cheaper.
ABSTRACT
BACKGROUND: Pulmonary artery hypertension (PAH) is a known complication of patients with sickle cell disease (SCD). The prevalence of PAH has been reported to be high in children with SCD in developed countries. The mortality rate of patients with SCD who develop PAH is said to be 40% at 24 to 40 months after diagnosis. In Sub-Saharan Africa, particularly Nigeria, where the prevalence of SCD is high, there is a dearth of data on the prevalence of PAH in children with SCD. PAH may be a likely contributor to the unacceptably high mortality rate of children with SCD in Africa. The present study aimed to determine the pattern of pulmonary artery pressure in children with sickle cell anaemia (SCA) aged 1 to 12 years in their steady state using Doppler echocardiography in our environment. METHODS: Analytical, comparative and cross-sectional study. It was carried out at Lagos State University Teaching Hospital (LASUTH) over a period of seven months (31st August 2015 through 31st March 2016). A total of 400 children, aged 1 to 12 years were recruited following parental consent and assent. Two hundred children with SCA in steady state and 200 age and sex matched children with haemoglobin genotype AA who served as controls were studied. All subjects and controls had Doppler echocardiography performed on them by the author. PAH was defined as a pulmonary artery systolic pressure (PASP) of ≥30 mmHg at rest derived from the tricuspid regurgitant velocity (TRV) measured from Doppler echocardiography. This corresponds with TRV value of ≥2.5 m/s. RESULTS: The prevalence of PAH in children with SCA was 8% (n=16). None of the controls had PAH. The youngest subject with PAH was aged 2 years. The overall mean pulmonary artery pressure of children with SCA was significantly higher than that of controls (18.54±5.81 vs. 13.76±5.71 mmHg, P=0.000). The prevalence of PAH in children with SCA demonstrated an increase in trend with age. CONCLUSIONS: The prevalence of PAH in children with SCA in steady state is high. This complication was noticed as early as the second year of life. It is recommended that all children with SCA should have periodic Doppler echocardiography for early detection of PAH.
