Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The increasing incidence of vitamin A toxicity is related to vitamin A supplementation for unfounded reasons. This article describes the common symptomatology of vitamin A toxicity, including hypercalcemia, hepatomegaly, and dermatological and neurological effects. Retinol supplements, but not carotene supplements, become toxic when free retinol circulates. Responsibilities of health professionals include questioning vitamin use when taking health histories, educating themselves with scientifically based nutritional studies and applying RDAs (recommended daily allowances) when advising clients.
 ...
PMID:The recognition and treatment of hypervitaminosis A. 267 24

In 42 myeloma patients our results confirm the association of light chain proteinuria and renal damage, but suggest that while the amount of light chain excreted is an important factor, only some light chains are nephrotoxic. The excretion of the proximal tubular cell lysosomal enzyme N acetyl B D glucosaminidase was a sensitive index of tubular injury, while the presence of low molecular weight proteinuria (Retinol Binding Protein and Lysozyme) was shown to indicate tubular dysfunction in a kidney sufficiently damaged to produce an impaired GFR. Isolated defects of distal tubular function (acid load response and concentrating ability) were rare. Such changes were seen mainly as part of global renal impairment and were usually associated with such specific pathophysiological conditions as plasma hyperviscosity or tubular crystal deposition. Hypercalcemia had a specific effect on the concentrating ability independent of any impairment of renal acidification.
 ...
PMID:Tubular function in multiple myeloma. 393 70

Serum vitamin A concentrations were measured in 38 patients undergoing haemodialysis, 24 of whom were taking multivitamin preparations containing vitamin A. Vitamin A concentrations were significantly higher in patients undergoing haemodialysis than in 28 normal controls (p less than 0.001). Patients taking vitamin A supplements had significantly higher vitamin A concentrations than those not taking them (p less than 0.05), and hypercalcaemic patients had higher concentrations than normocalcaemic patients (p less than 0.005). Withdrawal of vitamin A supplements in seven patients caused significant falls in serum vitamin A concentrations and plasma calcium concentrations (p less than 0.01 at two and three months in both cases) and in plasma alkaline phosphatase concentrations (p less than 0.01 at two months). Vitamin A toxicity can contribute to hypercalcaemia in patients undergoing haemodialysis, probably by an osteolytic effect. Multivitamin preparations containing vitamin A should therefore be prescribed with caution in these patients.
 ...
PMID:Vitamin A toxicity and hypercalcaemia in chronic renal failure. 678 64

Vitamin A toxicity produces protean clinical manifestations involving a wide variety of tissues and systems. Hypercalcemia can occasionally be associated with high vitamin A levels, but is rare. In this report we describe a patient who was receiving a commercially prepared enteral feeding formula for 2 years. He developed asymptomatic hypercalcemia and had serum vitamin A levels several fold above normal. Subsequently, a custom-made enteral feed was used which contained negligible amounts of vitamin A. Several months later, vitamin A levels diminished substantially and serum calcium levels returned to normal.
 ...
PMID:Hypercalcemia caused by iatrogenic hypervitaminosis A. 1563 57

Vitamin A intoxication secondary to over-the-counter nutritional supplements and from its use in acne treatment has been described. However, there have been very few case reports of chronic hypervitaminosis A leading to hypercalcemia in the pediatric population. This paper describes a boy with hypercalcemia secondary to chronic vitamin A intoxication in the context of vitamin A usage for therapy of autism. In addition to discontinuation of vitamin A, hyperhydration, and furosemide, the hypercalcemia in this patient required the use of prednisone and pamidronate to normalize the calcium.
 ...
PMID:Case of hypercalcemia secondary to hypervitaminosis a in a 6-year-old boy with autism. 2293 83

Vitamin A toxicity is a well-described medical condition with a multitude of potential presenting signs and symptoms. It can be divided into acute and chronic toxicity. Serum vitamin A concentrations are raised in chronic renal failure even with ingestion of less than the usual toxic doses. Hypercalcaemia can occasionally be associated with high levels of vitamin A but it is rare. In this report, we describe a 67- year old female patient with chronic kidney disease who was taking vitamin A supplements for approximately 10 years. The patient had worsening of her chronic kidney disease over the last years and developed chronic hypercalcaemia. Her vitamin A level was elevated with a daily intake of 7000 IU. The vitamin A supplement was stopped. A few months later, vitamin A level diminished substantially and serum calcium levels returned to normal.
...
PMID:Hypercalcaemia secondary to hypervitaminosis a in a patient with chronic renal failure. 2530 2

Objectives Vitamin A is essential for normal cellular physiology and is often taken as a dietary supplement. Hypervitaminosis A can lead to hypercalcemia by increasing osteoclasts and subsequent bone resporption. Dietary supplements including vitamin A are new popular treatment stategies for autism. Case presentation We report a five-year old boy with autism spectrum disorder presenting with severe abdominal pain and bilateral lower extremity pain, who was found to have persistent hypercalcemia due to hypervitaminosis A. The patient ingested over 700 times the recommended intake of Vitamin A per day for age. Retention of vitamin A in the liver and adipose tissue causes toxic levels of retinoids and hypercalcemia. Conclusions Acute treatment included intravenous rehydration, furosemide, and calcitonin. Pamidronate was the definitive treatment for hypercalcemia from hypervitaminosis A due to its osteoclast inhibition and long biologic half-life. Parents should be counseled on risks of toxicity and absence of evidence showing benefits of vitamin A therapy for autism.
 ...
PMID:Hypercalcemia from hypervitaminosis A in a child with autism. 3265 63