title: Serum ionized calcium, serum and intracellular phosphate, and serum parathormone concentrations in acute malaria.
abstract: Previous studies have shown depressed serum corrected calcium and phosphate concentrations in acute falciparum malaria. To characterize malaria-associated disturbances in mineral homoeostasis further, serum ionized calcium and intracellular phosphate were measured in 18 patients (10 with falciparum malaria, 8 with vivax malaria) and 10 healthy controls. Six patients (4 falciparum, 2 vivax) had admission serum ionized calcium concentrations below the absolute control range (< 1.15 mmol/litre) and a further six (3 falciparum, 3 vivax) developed ionized hypocalcaemia during treatment. The patients with falciparum malaria had the lowest values at presentation (median [95% confidence intervals in brackets]: 1.17 [1.12-1.23] vs. 1.20 [1.18-1.24] mmol/litre in controls, P = 0.035) in the presence of depressed simultaneous serum parathormone concentrations (1.2 [0.6-1.9] vs. 1.6 [1.1-2.6] pmol/litre; P = 0.05). Admission serum phosphate concentrations were lower in the malaria patients (P = 0.007 vs. controls), especially in those with falciparum malaria (0.85 [0.7-1.1] vs. 1.2 [1.1-1.3] mmol/litre in controls; P = 0.002); patients with falciparum malaria also had significantly lower intracellular phosphate than controls (0.74 [0.58-0.90] vs. 0.88 [0.66-1.04] mmol/litre red cells; P = 0.047). There was a weak association between serum corrected and ionized calcium in the malaria patients (rs = 0.31, n = 18, P > 0.1), but serum and intracellular phosphate correlated significantly (rs = 0.71, n = 17, P < 0.001) with a regression line slope of 0.49 and intercept of 0.27 mmol/litre of red cells.(ABSTRACT TRUNCATED AT 250 WORDS)
authors: University of Western Australia, Department of Medicine, Fremantle Hospital.
authors: T M
authors: TM
authors: Davis
authors: G Q
authors: GQ
authors: Li
authors: X B
authors: XB
authors: Guo
authors: J L
authors: JL
authors: Spencer
authors: A
authors: A
authors: St John
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D002118:Calcium / Q000097:blood*; D002648:Child; D004912:Erythrocytes / Q000737:chemistry; D005260:Female; D006801:Humans; D007424:Intracellular Fluid / Q000737:chemistry; D016778:Malaria, Falciparum / Q000097:blood*; D016780:Malaria, Vivax / Q000097:blood*; D008297:Male; D010281:Parathyroid Hormone / Q000097:blood*; D010710:Phosphates / Q000097:blood*
chemical_list: D010281:Parathyroid Hormone; D010710:Phosphates; D002118:Calcium