Serum reference intervals of micronutrients, vitamins, and interleukins among healthy adults in South-Western Nigeria.

Objectives: Clinical decision making depends mostly on appropriate application of numerical pathology reports from laboratory results, interpreted by comparison with reference intervals. We determined serum reference intervals of micronutrients, vitamins, and detectable interleukins among healthy adults in South-Western Nigeria. Design and methods: This prospective study used a priori selection approach in blood-donors. They were screened for conditions that could elicit cytokine production.Serum micronutrients were assayed using Atomic Absorption Spectrophotometry; interleukins and vitamins by high Performance Liquid Chromatography. The reference intervals (RIs) were estimated at 2.5th percentile and 97.5th percentile. Results: One hundred and eighteen (118) apparently healthy subjects, aged 18-56 years; 113 (95.8%) being 18-44years, and 5 (4.2%): 45-56 years; mostly males, 13 (11.02%) females, all Africans of Yoruba ethnicity.Estimated reference limits were: Zinc: 9.49-20.54 µmol/L, Selenium: 0.50-1.11 µmol/L, Copper: 13.86-27.97 µmol/L, Iron: 14.19-32.07 µmol/L, Manganese: 6.24-16.37 nmol/L; Magnesium: 0.78-1.62 mmol/L.Vitamins: A-1.08-2.39 µmol/L; D: 59.89-164.42 µmol/L; E: 7.13-19.45 µmol/L; K: 0.16-0.42 nmol/L; B1: 74.09-201.56 nmol/L; B6: 0.12-0.29 nmol/L; B12: 155.55-407.96 pmol/L; C: 47.74-112.99 µmol/L.Detected interleukins (IL-1 to IL-18): IL-1: 0.58-1.24 ng/L, IL-2: 0.09-0.18 ng/L, IL-3: 0.39-0.89 ng/L, IL-4: 0.27-0.58 ng/L, ….to IL-18: 0.74-1.56 ng/L. Conclusions: The RI derived from this study for serum micronutrient, vitamin and interleukin concentrations are the first published for our population. They are in general agreement with those published from other geographical climes but there are differences at the lower and upper limits of the RI. The study reinforces the importance of deriving RI for the population that a clinical laboratory will serve.

Serum Interleukin-6 and Weight Loss in Antiretroviral-naïve and Antiretroviral-treated Patients with HIV/AIDS: Relationships and Predictors.

BACKGROUND: Cachexia is usually associated with elevated serum interleukin-6 (IL.6) as it stimulates the breakdown of muscle proteins and promotes wasting. OBJECTIVE: A case-control study to evaluate the relationship between weight loss, facial fat loss, and IL-6 in antiretroviral-naïve and treated participants living with HIV/AIDS. METHODS: IL-6 was assayed by High performance liquid chromatography (HPLC) in 97 in consecutive newly diagnosed antiretroviral-naive (ART-naïve) people living with HIV/AIDS (age ≥18 years); and 118 consecutive, age-matched participants currently on Highly Active Antiretroviral Therapy (HAART), using age as a criterion. In the treated group, 78 (66.7%) subjects were on zidovudine, lamivudine with nevirapine (Z+L+N); 27(23.1%) on tenofovir, lamivudine with emtricitabine (T+L+E); 5(4.3%) on zidovudine, lamivudine with emtricitabine (Z+L+E); 4(3.4%) on zidovudine, lamivudine with tenofovir (Z+L+T); 2(1.7%) on lamivudine, tenofovir with nevirapine (L+T+N); 1(0.9%) on tenofovir, zidovudine, emtricitabine (Z+T+E). RESULTS: A total of 215 participants: 97 ART-naive and 118 HAART-treated, age-matched subjects (40.3±9.6 versus 42.7±10.20years, p=0.08). The mean IL-6 was significantly higher in naïve than treated (0.69±0.04 versus 0.66±0.04 pg/ml, p =0.002). In all, 73 subjects experienced weight loss, 56(76.7%) naive, 17(23.3%) treated, p <0.0001, with significantly higher IL-6 in those with weight loss (0.69±0.05 versus 0.67±0.05pg/ml, p= 0.047). Fifty-eight (27.0%) subjects experienced facial fat loss, 49 (84.5%) naïve, and 9 (15.5%) treated, p <0.0001, with significantly higher IL-6 in those with facial fat loss (0.7 ± 0.05 versus 0.67±0.05pg/ml, p= 0.0001). Negative correlation exists between IL-6 and CD4+ count (r=-0.141, p=0.041). In logistic regression, independent predictors of weight loss include: IL-6 (Adjusted Odds Ratio, aOR 1.3, 95%CI 0·1-2·6, p=0.047); HIV duration (aOR 11.6, p <0.0001); AIDS-defining illness (aOR 3.5, p <0.0001); CD4+ count (aOR 3.2, p=0.004); HAART status (aOR 2.7, p<0.0001). CONCLUSION: HIV infection is associated with elevation of serum interleukin-6, which likely contributes to weight and facial fat loss among the treatment-naïve participants; while HAART is associated with suppressed IL-6 levels, thereby ameliorating weight and facial fat loss. Inverse relationship exists between serum IL-6 and CD4+ count; serum IL-6 could differentiate between mild- to moderate and severe immunosuppressive states.

Serum Zinc, Selenium and Total Antioxidant Contents of Nigerian Children with Asthma: Association with Disease Severity and Symptoms Control.

BACKGROUND: Micronutrients and antioxidants may ameliorate oxidative stress. This study aimed to determine the serum Zinc (Zn), Selenium (Se) and Total Antioxidant Contents (TAC) of Nigerian children with asthma and relate these to disease severity and symptoms control. METHODS: Children aged 2-15 years with asthma and age and sex matched controls were consecutively recruited. The children's serum Zn, Se and TAC were assayed and compared. RESULTS: Eighty children each with asthma and controls participated in the study. Serum Zn (71.0 ± 30.3 µg/dl vs. 84.2 ± 31.7 µg/dl; p = 0.008), Se (67.3 ± 29.8 µg/l vs. 80.0 ± 31.7 µg/l; p = 0.033) and TAC [median (interquartile range) 5.2 (3.8-6.8) ng/dl vs. 6.2 (4.3-8.0) ng/dl; p = 0.019] were lower in children with asthma. Serum Se (65.7 ± 29.1 µg/l vs. 92.4 ± 28.6 µg/l; p = 0.001) was lower in those with moderate/severe than mild disease, but no association with symptoms control (p > 0.05). CONCLUSION: Micronutrient supplementation may be beneficial in Nigerian children with asthma as they have relatively lower antioxidant micronutrients than nonasthmatics.

Acute chest syndrome in sickle cell anaemia: higher serum levels of interleukin-8 and highly sensitive C-reactive proteins are associated with impaired lung function.

BACKGROUND: Sickle cell anaemia (SCA) is a chronic inflammatory disorder with multiple organ manifestations including acute and long-term pulmonary dysfunction. AIMS/OBJECTIVES: To assess lung function of children with SCA and determine the possible role of acute chest syndrome (ACS), serum inflammatory cytokines, highly sensitive C-reactive protein (hs-CRP), leucocytes and 25-hydroxyvitamin D on the development of impaired lung function. SUBJECTS AND METHODS: Lung function of 76 children with SCA was determined by spirometer and classified into normal or impaired. Sociodemographic, clinical, haematological, biochemical and immunological data of the two groups were compared by univariate and multivariate analyses. RESULTS: Fifty (65.8%) patients had impaired lung function, comprising of 30.3%, 3.9% and 31.6% with restrictive, obstructive and mixed disease patterns, respectively. Children with previous ACS were 3.6 times more likely to have impaired lung function than those without ACS (82.1% vs 56.3%, p = 0.02, OR 3.6, 95% CI 1.2-10.8). Interleukin (IL)-8 and hs-CRP were significantly higher in patients with impaired lung function (p = 0.02 and <0.001, respectively). Using logistic regression, previous ACS (OR 5.8, 95% CI 1.1-5.8, p = 0.03) and higher serum IL-8 levels (OR 3.0, 95% CI 1.0-8.0, p = 0.02) independently predicted the presence of abnormal lung function. CONCLUSIONS: Lung dysfunction, predominantly restrictive pattern, is common in SCA and is associated with previous ACS and alterations in immunological markers, especially serum IL-8 and hs-CRP. ABBREVIATIONS: ACS: acute chest syndrome; CBT: chronic blood transfusion; ELISA: enzyme-linked immunosorbent assay; FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; HPLC: high-density liquid chromatography; hs-CRP: highly sensitive C-reactive proteins; HU: hydroxyurea; IL: Interleukin; PEFR: peak expiratory flow rate; SEM: standard error of the mean; TLC: total lung capacity; 25-OHD: 25-hydroxyvitamin D; VOC: vaso-occlusive crisis; WGH: Wesley Guild Hospital.

Relationship between serum 25-hydroxyvitamin D and inflammatory cytokines in paediatric sickle cell disease.

BACKGROUND: Alteration in the concentration of inflammatory cytokines may contribute to pathogenesis in sickle cell anaemia (SCA). Vitamin D may suppress pro-inflammatory cytokines and enhance anti-inflammatory cytokines. OBJECTIVE: To compare steady state levels of pro-and anti-inflammatory cytokines of Nigerian SCA children with age- and sex-matched healthy controls, and determine the relationship with 25-hydroxyvitamin-D (25-OHD). Effects of three months of vitamin D supplementation on cytokines of SCA children with suboptimal 25-OHD were also evaluated. METHODS: Serum 25-OHD, IL-1ß, 2, 6, 8, 11, 12, 13, 17, 18 of 95 SCA children and 75 matched controls were determined using HPLC. The 12 SCA children with suboptimal 25-OHD received 2000IU of vitamin D daily for 3months, and their post supplementation cytokines and 25-OHD levels were compared with the baseline values. RESULTS: IL-2, 6, 8, 12, 17 and 18 were higher in SCA children than the controls (p≤0.001), but no significant variation in IL-11 and 13 (p=0.131 and 0.057 respectively). Patients with suboptimal serum 25-OHD had higher IL-6, 8 and 18 (p=0.003, 0.010 and 0.002 respectively) and lower levels of IL-11 (p=0.005). Significant positive treatment effects were observed: post-supplementation, serum 25-OHD increased by 23.3ng/mL, p<0.001; proinflammatory cytokines IL-2, 6, 8, 17 and 18 (p<0.001) were reduced and anti-inflammatory cytokine IL-11 was increased, p<0.001. CONCLUSIONS: Suboptimal 25OHD is associated with enhanced levels of pro-inflammatory markers in children with SCA. Three months of daily vitamin D supplementation reversed the trend. Hence; Vitamin D supplementation may reduce the inflammatory milieu and serve as an anti-inflammatory agent in the management of SCA.