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Abstract
Background: Nutritional rickets remains a common cause of skeletal deformities among children in developing countries. While vitamin D deficiency is traditionally implicated, evidence from tropical regions with abundant sunlight suggests calcium deficiency may be more prominent.
Objectives: This study evaluated the relative roles of calcium and vitamin D in children with rickets in Ekiti, Southwestern Nigeria.
Methods: A descriptive comparative study was conducted involving 32 children with clinical features of rickets and 32 age- and sex-matched controls without rickets at Ekiti State University Teaching Hospital, Ado-Ekiti. Sociodemographic and clinical data were collected, and biochemical analyses included serum calcium, phosphate, alkaline phosphatase (ALP), vitamin D, total protein, albumin, and renal function tests. Radiographs of wrists and knees were obtained for affected children. Independent sample t-tests compared mean biochemical values, while Chi-square tests assessed associations between variables. Statistical significance was set at p < 0.05.
Results: The mean age of affected children was 3.06 ± 0.13 years (range 2–5 years). Bilateral genu varum was the most common presentation (31.3%). Hypocalcaemia was observed in 87.5% of cases and elevated ALP in 75.0%, whereas 87.5% had normal serum vitamin D levels. Significant differences between cases and controls were found for serum calcium (p = 0.02) and ALP (p = 0.01), but not for vitamin D or protein levels. Renal parameters were largely normal.
Conclusion: Calcium deficiency appears to be the predominant biochemical abnormality in children with rickets in this tropical setting, despite adequate sunlight exposure and largely normal vitamin D levels. Emphasis on calcium assessment and supplementation is essential for effective management and prevention.
Keywords:
Nutritional rickets, calcium deficiency, vitamin D, alkaline phosphatase, tropical region, Nigeria.
References
Rajakumar K. Vitamin D, cod-liver oil, sunlight, and rickets: a historical perspective. Pediatrics. 2003;112(2):e132-e135. Accessed September 27, 2025. https://publications.aap.org/pediatrics/article-abstract/112/2/e132/63266
Hess AF, Unger LJ. Infantile rickets: the significance of clinical, radiographic and chemical examinations in its diagnosis and incidence. American Journal of Diseases of Children. 1922;24(4):327-338. Accessed September 27, 2025. https://jamanetwork.com/journals/jamapediatrics/article-abstract/1173809
McCollum EV, Simmonds N, Becker JE, Shipley PG. Studies on experimental rickets: XXI. An experimental demonstration of the existence of a vitamin which promotes calcium deposition. Journal of biological Chemistry. 1922;53(2):293-312. Accessed September 27, 2025. https://www.sciencedirect.com/science/article/pii/S0021925818857830
Chick H. The discovery of vitamins. Published online 1975. Accessed September 27, 2025. https://www.cabidigitallibrary.org/doi/full/10.5555/19781465558
Levy-Litan V, Hershkovitz E, Avizov L, et al. Autosomal-recessive hypophosphatemic rickets is associated with an inactivation mutation in the ENPP1 gene. The American Journal of Human Genetics. 2010;86(2):273-278. Accessed September 27, 2025. https://www.cell.com/AJHG/fulltext/S0002-9297(10)00013-3
Creo AL, Thacher TD, Pettifor JM, Strand MA, Fischer PR. Nutritional rickets around the world: an update. Paediatrics and International Child Health. 2017;37(2):84-98. doi:10.1080/20469047.2016.1248170
Carpenter TO, Shaw NJ, Portale AA, Ward LM, Abrams SA, Pettifor JM. Rickets. Nature Reviews Disease Primers. 2017;3(1):1-20. Accessed September 27, 2025. https://www.nature.com/articles/nrdp2017101
Cianferotti L. Osteomalacia is not a single disease. International Journal of Molecular Sciences. 2022;23(23):14896. Accessed September 27, 2025. https://www.mdpi.com/1422-0067/23/23/14896
Wharton B, Bishop N. Rickets. The Lancet. 2003;362(9393):1389-1400. Accessed September 27, 2025. https://www.thelancet.com/journals/lancet/article/PIIS0140673603146363/abstract
Wagner CL, Greer FR, Breastfeeding S on, Nutrition C on. Prevention of rickets and vitamin D deficiency in infants, children, and adolescents. Pediatrics. 2008;122(5):1142-1152. Accessed September 27, 2025. https://publications.aap.org/pediatrics/article-abstract/122/5/1142/71470
Orina LK, Walekhwa M, Chege P. Inadequate Sunlight Exposure as A Risk Factor for Nutritional Rickets: A Systematic Review. African Journal of Nutrition and Dietetics. 2024;3(1):147-161. Accessed September 27, 2025. https://journals.mjmbiolabs.co.ke/index.php/AJND/article/view/90
Florin TA, Ludwig S. Netter’s Pediatrics. Elsevier Health Sciences; 2011. Accessed September 27, 2025. https://books.google.com/books?hl=en&lr=&id=7czRAQAAQBAJ&oi=fnd&pg=PP1&dq=Florin+T,+Stephen+L,+Aronson+PL,+Werner+HC+(2011).+Netter%27s+Pediatrics+E-Book.+Elsevier+Health+Sciences.+p.+430.&ots=THoo7nsHaT&sig=1cOkl9KtgHqy3L2CSUCri7va_6A
Oginni LM, Worsfold M, Oyelami OA, Sharp CA, Powell DE, Davie MWJ. Etiology of rickets in Nigerian children. The Journal of pediatrics. 1996;128(5):692-694. Accessed September 27, 2025. https://www.sciencedirect.com/science/article/pii/S0022347696801375
Greenbaum LA. Rickets and hypervitaminosis. Textbook of pediatrics. Published online 2007:253-263. Accessed September 27, 2025. https://cir.nii.ac.jp/crid/1570854176050799360
Ekbote VH, Khadilkar AV, Mughal MZ, et al. Sunlight exposure and development of rickets in Indian toddlers. Indian J Pediatr. 2010;77(1):61-65. doi:10.1007/s12098-009-0263-2
Khalil T. Prevalence of rickets among children below one-year encounter of North West Armed Forced Hospital in Tabuk. Int J Med Sci Public Health. 2014;3(7):827-831. Accessed September 27, 2025. http://journalsarchive.com/FILES/IJMSPH/12.%20Prevalence%20of%20Rickets%20among%20Children%20Below%20one-year%20encounter%20of%20North%20West%20Armed%20Forced%20Hospital%20in%20Tabuk,%202013.pdf
Mahmoud AO, Ahmed AY. The prevalence of active nutritional rickets in Egyptian infants in Cairo. Egyptian Pediatric Association Gazette. 2016;64(3):105-110. Accessed September 27, 2025. https://www.sciencedirect.com/science/article/pii/S1110663816300416
Tello M (2018). Vitamin D: What’s the ‘right’ level? Harvard Health Publishing - Google Search. Accessed September 27, 2025. https://www.google.com/search?client=firefox-b-d&q=Tello+M+%282018%29.+Vitamin+D%3A+What%E2%80%99s+the+%E2%80%98right%E2%80%99+level%3F+Harvard+Health+Publishing
Haffner D, Emma F, Seefried L, et al. Clinical practice recommendations for the diagnosis and management of X-linked hypophosphataemia. Nature Reviews Nephrology. 2025;21(5):330-354. Accessed September 27, 2025. https://www.nature.com/articles/s41581-024-00926-x
Iwegbu G. Orthopaedics and Trauma for Medical Students and Junior Residents. AuthorHouse; 2012. Accessed September 27, 2025. https://books.google.com/books?hl=en&lr=&id=012GU0gx-MQC&oi=fnd&pg=PP2&dq=The+Indolent+form+of+rickets+with+deformity+would+require+correction+of+the+biochemical+deficiencies+before+intervention,+while+the+burnt-out+rickets+with+deformity+in+the+older+children+might+be+treated+surgically+with+any+of+the+various+corrective+operations&ots=IWASqlRqFM&sig=zE4Ye6MFalkodkgo8Wa_lFtMIt8
Chiu KC, Chu A, Go VLW, Saad MF. Hypovitaminosis D is associated with insulin resistance and β cell dysfunction. The American journal of clinical nutrition. 2004;79(5):820-825. Accessed September 27, 2025. https://www.sciencedirect.com/science/article/pii/S0002916522039247
Kratz A, Ferraro M, Sluss PM, Lewandrowski KB (2004). Laboratory reference values. New England Journal of Medicine 351: 2461. - Google Search. Accessed September 27, 2025. https://www.google.com/search?q=Kratz+A%2C+Ferraro+M%2C+Sluss+PM%2C+Lewandrowski+KB+%282004%29.+Laboratory+reference+values.+New+England+Journal+of+Medicine+351%3A+2461.&client=firefox-b-d&sca_esv=ca0e7ba2501edfa5&sxsrf=AE3TifMJiHECNLd_jYaKlnPhlQUDcAfjKA%3A1759010735401&ei=r1_YaNWnGJeGhbIP3urriQg&ved=0ahUKEwiVu6jQ-fmPAxUXQ0EAHV71OoEQ4dUDCBA&uact=5&oq=Kratz+A%2C+Ferraro+M%2C+Sluss+PM%2C+Lewandrowski+KB+%282004%29.+Laboratory+reference+values.+New+England+Journal+of+Medicine+351%3A+2461.&gs_lp=Egxnd3Mtd2l6LXNlcnAifUtyYXR6IEEsIEZlcnJhcm8gTSwgU2x1c3MgUE0sIExld2FuZHJvd3NraSBLQiAoMjAwNCkuIExhYm9yYXRvcnkgcmVmZXJlbmNlIHZhbHVlcy4gTmV3IEVuZ2xhbmQgSm91cm5hbCBvZiBNZWRpY2luZSAzNTE6IDI0NjEuMgcQIxgnGOoCMgcQIxgnGOoCMgcQIxgnGOoCMgcQIxgnGOoCMgcQIxgnGOoCMgcQIxgnGOoCMgcQIxgnGOoCMgcQIxgnGOoCMgcQIxgnGOoCMgcQIxgnGOoCSJQ1UJgaWJgacAJ4AZABAJgBAKABAKoBALgBA8gBAPgBAfgBApgCAqAChgKoAgqYA7QB8QX5P1UyAfqHgpIHAzEuMaAHALIHALgHAMIHBTUtMS4xyAexAQ&sclient=gws-wiz-serp
Akpede GO, Solomon EA, Jalo I, Addy EO, Banwo AI, Omotara BA. Nutritional rickets in young Nigerian children in the Sahel savanna. East African medical journal. 2001;78(11):568-575. Accessed September 27, 2025. https://www.ajol.info/index.php/eamj/article/view/8945/1551
Solomon L. Metabolic and endocrine disorders. In: Apley’s System of Orthopaedics and Fractures. CRC Press; 2010:135-168. Accessed September 27, 2025. https://www.taylorfrancis.com/chapters/edit/10.1201/b13422-14/metabolic-endocrine-disorders-louis-solomon
