II. Epidemiology
III. Precautions
-
Vitamin D Testing has increased substantially increased since 2010, often for vague, unrelated symptoms
- Low Vitamin D levels result in a cascade of additional tests and referrals
- However, levels are often inaccurate, variable and with no universal defined lower limit of normal
-
Vitamin D Replacement (esp. high dose) for asymptomatic, low Vitamin D typically offers little benefit
- Contrast with truly indicated replacement in severe Vitamin D Deficiency (e.g. Rickets, Osteomalacia)
- References
IV. Risk Factors: Infants
- Anticonvulsants
- Chronic disease with fat malabsorption
- Exclusively Breast-fed infant without Vitamin D Supplementation
- Low maternal Vitamin D levels
- Lack of Sun Exposure
- Direct sunlight avoidance is recommended by AAP for those under 6 months
- Darker skin pigmentation (requires 3-6 fold more Sun Exposure)
V. Risk Factors: Adults
- Age over 65 years
- Related to housebound status and decreased Vitamin D absorption
- Comorbid illness
- Malnourished
- Total Parenteral Nutrition
- Lack of Sun Exposure (or thorough sun screen use)
- Those with darker skin require 3-6 fold more exposure
- Renal disease (Renal Failure, Nephrotic Syndrome)
- Renal losses of Vitamin D
- Hepatic disease (Cirrhosis)
- Gastrointestinal malabsorption
- Gastric surgery (resection or Gastric Bypass)
- Crohn's Disease
- Cystic Fibrosis
- Celiac Disease
- Small Bowel Resection
- Medications
- Anticonvulsant use (e.g. Phenobarbital, Phenytoin)
- Requires 2-5 fold more Vitamin D intake daily
- Corticosteroids (long-term use) or other Immunosuppressants
- Rifampin
- Antiviral Medications
- Anticonvulsant use (e.g. Phenobarbital, Phenytoin)
VI. Pathophysiology
- Effects of Vitamin D Deficiency
- Altered secretion of Parathyroid Hormone
- Altered mineral ion metabolism
- Mineralization defects in skeleton
- Osteomalacia in adults
- Rickets in children
- Step-by-step outcome of Vitamin D Deficiency
- Malabsorption of Calcium and Phosphorus
- Calcium absorption drops to 10% of normal
- Phosphorus absorption drops to 60% of normal
- Inadequate intestinal Calcium absorption
- Results in Hypocalcemia
- Severe Hypocalcemia occurs in later deficiency
- PTH secreted to compensate for Hypocalcemia
- Results in secondary Hyperparathyroidism
- Osteoclasts dissolve bone to mobilize Calcium from bone
- Exacerbates Osteomalacia and Osteoporosis
- Increased PTH results in phosphate wasting
- Severe hypophophatemia results
- Malabsorption of Calcium and Phosphorus
VII. Symptoms
- Early
- Diffuse Myalgias (may be associated marked serum Creatine Phosphokinase or CPK elevations)
- Proximal Muscle Weakness
- Associated with increased Fall Risk
- Later
- Bone pain
- Low Back Pain (especially older women)
- Extremity pain
- Secondary Hyperparathyroidism
- Symptomatic mineral disturbance
- See Hypocalcemia
- See Hypophosphatemia
- Bone pain
- Other symptoms
VIII. Signs
- Bone pain reproduced with pressure applied to Sternum or tibia
IX. Differential Diagnosis
- See Hypocalcemia
- See Hypophosphatemia
- See Hyperparathyroidism
- Myalgias
- See Polymyositis Differential Diagnosis
- Consider in those diagnosed with Fibromyalgia, Myositis, Malingering
X. Associated Conditions: Conditions linked to Vitamin D Deficiency
- Musculoskeletal Conditions
- Other associated conditions (but insufficient evidence that supplementation prevents these conditions)
- Fall Risk
- Cardiovascular Disease
- Colon Cancer
- Major Depression
XI. Labs
- Serum 25-Hyroxyvitamin D Level
- Routine screening is not recommended
- Vitamin D testing or supplementation is not indicated in Major Depression, Fatigue, Osteoarthritis or Chronic Pain
- Preferred test (but expensive)
- Levels <20 ng/ml suggest deficiency (<30 ng/ml per endocrine society)
- Ionized Serum Calcium
- Serum Phosphorus
- Serum Creatine Phosphokinase
- May increase significantly in Vitamin D Deficiency with myalgias
- Consider testing for Vitamin D Deficiency mimics in Differential Diagnosis
- Thyroid Stimulating Factor
- Rheumatoid Factor
- Serum Vitamin B12
XII. Management
- Treat Hypocalcemia
- Symptomatic Hypocalcemia or Ionized Calcium <3.2 mg/dl
- Treat Hypophosphatemia
- Vitamin D Replacement
-
Vitamin D maintenance
- Guidelines do not recommend routine Vitamin D screening (outside Hypercalcemia, Renal Insufficiency)
- Maintain Vitamin D at least above 20 ng/ml (and >29 ng/ml per endocrine society)
- See Vitamin D for maintainance doses
XIII. Prevention
- Adequate dosing depends on latitude
- In northern climates 1000-2000 IU daily may be more appropriate
- Higher doses may be required in those with risk factors above
XIV. References
- Rendon et al. (2017) Crit Dec Emerg Med 31(6): 15-21
- Bordelon (2009) Am Fam Physician 80(8): 841-6 [PubMed]
- Holick (2007) N Engl J Med. 357(3):266-81 [PubMed]
- Holick (2008) Am J Clin Nutr 87:1080S-1086S [PubMed]
- LeFevre (2018) Am Fam Physician 97(4): 254-60 [PubMed]
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Definition (CSP) | condition due to a deficiency of vitamin D. |
Definition (MSH) | A nutritional condition produced by a deficiency of VITAMIN D in the diet, insufficient production of vitamin D in the skin, inadequate absorption of vitamin D from the diet, or abnormal conversion of vitamin D to its bioactive metabolites. It is manifested clinically as RICKETS in children and OSTEOMALACIA in adults. (From Cecil Textbook of Medicine, 19th ed, p1406) |
Concepts | Disease or Syndrome (T047) |
MSH | D014808 |
ICD9 | 268.9, 268 |
ICD10 | E55 , E55.9 |
SnomedCT | 190649007, 154728003, 190639009, 124886009, 34713006 |
English | Deficiencies, Vitamin D, Deficiency, Vitamin D, Vitamin D Deficiencies, Unspecified vitamin D deficiency, VITAMIN D DEFICIENCY, Avitaminosis D NOS, Vitamin D deficiency, unspecified, DEFIC VITAMIN D, VITAMIN D DEFIC, vitamin D deficiency, vitamin D deficiency (diagnosis), avitaminosis D, avitaminosis D (diagnosis), Vitamin D deficiency NOS, Vitamin D Deficiency [Disease/Finding], d deficiencies vitamin, deficiency vitamin d, vitamin d deficiencies, d deficiencies vitamins, d deficiency vitamin, vitamin d deficiency, d deficiency vitamins, d vitamin deficiency, Avitaminosis D NOS (disorder), Deficiency of vitamin D (disorder), Hypovitaminosis D, Vitamin D Deficiency, Vitamin D deficiency, Avitaminosis D, Vitamin D deficiency (disorder), deficiency; vitamin, D, vitamin; deficiency, D, Avitaminosis D, NOS, Vitamin D deficiency, NOS |
German | VITAMIN-D-MANGEL, unspezifischer Vitamin D-Mangel, Vitamin-D-Mangel, nicht naeher bezeichnet, Vitamin D-Mangel, Vitamin-D-Mangel |
Dutch | niet-gespecificeerde vitamine-D-deficiëntie, deficiëntie; vitamine, D, vitamine; deficiëntie, D, Vitamine D-deficiëntie, niet gespecificeerd, vitamine-D-deficiëntie, Vitamine D-deficiëntie, Vitamine-D-gebrek, Deficiëntie, vitamine-D-, Vitamine-D-deficiëntie |
French | Carence en vitamines D non précisée, CARENCE EN VITAMINE D, Déficit en vitamine D, Carence en vitamine D, Carence en vit D |
Italian | Carenza non specificata di vitamina D, Carenza di vitamina D |
Portuguese | Carência de vitamina D NE, CARENCIA EM VITAMINA D, Carência de vitamina D, Deficiência de Vitamina D |
Spanish | Déficit no especificado de vitamina D, VITAMINA D, DEFICIT, déficit de vitamina D (trastorno), avitaminosis D, SAI, avitaminosis D, SAI (trastorno), avitaminosis D, deficiencia de vitamina D, hipovitaminosis D (trastorno), hipovitaminosis D, Déficit de vitamina D, Deficiencia de Vitamina D |
Japanese | ビタミンD欠乏、詳細不明, ビタミンD欠乏, ビタミンDケツボウショウサイフメイ, ビタミンDケツボウ, ビタミンD欠乏症 |
Swedish | Vitamin D-brist |
Finnish | D-vitamiinin puutos |
Russian | VITAMINA D NEDOSTATOCHNOST', ВИТАМИНА D НЕДОСТАТОЧНОСТЬ |
Czech | Blíže neurčený deficit vitaminu D, Deficit vitaminu D, vitamin D - nedostatek, nedostatek vitaminu D |
Korean | 상세불명의 비타민 D 결핍증, 비타민 D 결핍증 |
Croatian | Not Translated[Vitamin D Deficiency] |
Polish | Hipowitaminoza D, Niedobór witaminy D |
Hungarian | Nem meghatározott D-vitamin hiány, D-vitamin hiány |
Norwegian | D-vitaminmangel, Vitamin D-mangel |