In an 8 yr old girl with symptoms of rickets, lab investigations show Serum Calcium 7.2 mg/dl, Serum Phosphates 2.3 mg/dl Alkaline Phosphatase 2420 IU/L. The most probable diagnosis is?
ANSWER: (C) Nutritional RicketsREF: Nelson 17th edition page 2342 Table 691-2Table 691-2 Clinical variants of Rickets and Related ConditionsTypeSerum calcium LevelSerumPhosphorusLevelAlkaline Phosphatase ActivityUrine Concentration of Amino AcidsGeneticsI. Calcium deficiency with secondary hyperparathyroidism (deficiency of vitamin D; low 25(OH) D and no stimulation of higher 1,25 (OH)2 D values)1. Lack of vitamin D a. Lack of exposure to sunlighN orLLE E b. Dietary deficiency of vitamin in DN orLLEE c. CongentialN or LLEE 2. Malabsorption of Vitamin DN or LLEE 3. Hepatic diseaseNorLLEE 4. Anticonvulsive drugsN or LLEE 5. Renal osteodystrophyN or LEEV 6. Vitamin D-dependent type ILN or LE EARII. Primary phosphate deficiency (no secondary hyperparathyroidism)1. Genetic primary hypophosphatemiaNLENXD2. Fanconi syndrome a. CystinosisNLEEARb. TyrosinosisNLEEARc. Lowe syndromeNLEEXRd. AcquiredNLEE 3. Renal tubular acidosis, type II proximalNLEN 4. Oneogenic hypophosphatemiaNLEN 5. Phosphate deficiency or malabsorption a. Parenteral hyperalimentationNLEN b. Low phosphate intakeNLEN III. End-organ resistance to 1.25(OH)2 D31. Vitamin D-dependent type II (Several variants)LL or NEEARIV. Related conditions resembling rickets1. HypophosphatasisNNLPhosphoet- hanolamine AR elevated 2. Metaphyseal dysostosis a. Jansen typeENENADb. Schmid typeNNNNADN = normal; L = low; E = elevated; V = variable; X = X-linked; A = Autosomal; D = dominant; R = recessive; Yes = Y.Rickets may be classified as calcium-deficient or phosphate-deficient rickets. The two types of rickets are distinguishable by their clinical manifestations (Table 691-2)In this case Serum Ca levels are low; Phosphate levels are low, while ALP levels are high.
Vitamin D dependant type II
Hypophosphatemic Rickets
Nutritional Rickets
Secondary Hyperparathyroidism
Vitamin D