ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel
  • »
  • Health»
  • Nutrition»
  • Nutritional Vitamins & Supplements

Osteomalacia And Hypervitaminosis D: Clinical Manifestations, Diagnosis And Treatment

Updated on February 22, 2014

Osteomalacia

Source

Etiology

Osteomalacia denotes those disorders where mineralization of newly formed bone matrix (osteoid) is defective.

Etiology: Osteomalacia may be of two different types.

  1. Nutritional inadequacy of vitamin D
  2. Vitamin D-resistant osteomalacia. This occurs in the following conditions:
    1. In renal tubular defects which produce hypophosphatemia and chronic metabolic acidosis.
    2. Chronic administration of diphenylhydantoin which leads to excessive metabolism of vitamin D.
    3. Osteoporosis
    4. After parathyroidectomy for osteitis fibrosa of hyperparathyroidism in which rapid formation of new bone outstrips bone resorption.

Osteomalacia In India

Source

Looser’s zones In Osteomalacia

Source

Codfish Vertebrae In Osteomalacia

Source

Clinical Presentations

Osteomalacia presents with vague pain which start as aches and pains insidiously, in the lumbar spine and thighs and spreading later to the arms and ribs. The pain is frequently felt over the bones themselves, and not at the joints. The pain is usually symmetrical and non-radiating and is accompanied by tenderness of involved bones. Proximal muscles are weak and there is difficulty in climbing up stairs and getting up from the squatting position. Occasionally, localized acute bone pain develops rapidly. These sites correspond to the development of pseudofractures. Classical radicular pain may develop due to compression fractures of the vertebra.

Physical signs include deformities, which may be missed if not specifically looked for. The usual deformities are triradiate pelvis and spinal kyphosis (due to action of gravity). Pathologic fractures due to weight bearing and avulsion of tendinous attachements may develop. Biochemical features resemble those of rickets.

Characteristic radiological features are the appearance of “pseudofractures” (Milkman’s lines and Looser’s zones). These are linear zones of decalcification which tend to be symmetrical and extend perpendicular to the cortex. The common sites are the pubic rami, ischium, the neck of the femur, the outer edge of the scapula, ribs and vertebrae. Occasionally, Looser’s zones may extend right across a long bone simulating complete fractures. They are called pseudofractures because the gap is bridges by uncalcified osteoid tissue. They do not reveal any discontibuity of bone clinically. The pseudofractures are caused by the decalcification along the course of the major arteries entering the bones especially in areas of muscular attachement, namely the adductor insertion on the pubic ramus and attachement of gluteal muscles to the trochanters of the femur.

Vertebral bones show compression and widening of intervertebral spaces to produce biconcave or “cod-fish” vertebrae.

However, in patients who develop osteomalacia secondary to renal tubular disorders or chronic renal failure, there is marked cortical thickening and increased density of trabeculae in spongy bone. The reason for this hyperosteosis is not clear. Despite the radiological appearances, the bone is abnormally brittle and prone to develop fractures.

Treatment: Nutritional osteomalacia responds well to daily administration of 2000 to 4000 IU of vitamin D (0.05 to 0.1 mg) for 6 to 12 weeks followed by maintenance doses of 200 to 400 IU daily. Adequate supplements of calcium are provided in the form of milk, 500 to 750 ml per day or calcium lactate tablets, 1g along with food.

Hypervitaminosis D

Prolonged administration of massive doses of vitamin D results in vitamin D intoxication. This causes hypercalcemia. Symptoms include nausea, vomiting, constipation, drowsiness and signs of renal impairment. Metastatic calcification occurs in several tissues including the kidneys, lungs, gastric mucosa and blood vessels. Renal function may deteriorate before other signs of toxicity are manifest. Subjects receiving high doses of vitamin D should have regular monitoring of serum calcium and if it is above 2.6 mmol/liter (10.5 mg/dal), the intake of the vitamin should be stopped.

© 2014 Funom Theophilus Makama

Comments

    0 of 8192 characters used
    Post Comment

    No comments yet.

    working

    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, hubpages.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: "https://hubpages.com/privacy-policy#gdpr"

    Show Details
    Necessary
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
    Features
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Marketing
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Statistics
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)