Monday, March 28, 2011


Which one of the following is NOT related to an elevated PTHrp level and leading to hypercalcemia? What you all answered:

SLE 29% 
Malignancy 6%
HIV associated Lympadenopathy 8%
Massive mammary hyperplasia during pregnancy 6%
Manganese toxicity 23%
During late pregnancy and lactation in hypoparathyrodism 25%

Close race between SLE, Manganese and Late pregnancy. Correct answer is Manganese toxicity. Rest of all are associated with pthrp production.

All above causes mentioned are rare causes of hypercalcemia to begin with.
Lets get to one by one.
We all know that malignancy such as ovary, lung and kidney can be associated with pthrp associated hypercalcemia.  SLE, HIV associated lymphadenopathy has also been associated with pthrp associated hypercalcemia.  Apparently, massive mammary hyperplasia during pregnancy, late pregnancy via placenta production of pthrp and lactation in hypoparathyroidism all have been associated with pthrp associated mechanism of hypercalcemia. The hypercalcemia associated with manganese toxicity is due to an unknown mechanism that we don't know( not pthrp).
Below are few causes that I saw in a very interesting article on rare causes of hypercalcemia.  Take a look.
Ref is below. 

**Rare causes of hypercalcemia associated with elevated 1,25-dihydroxyvitamin D
1. Wegener’s granulomatosis 
2. Cat scratch fever 
3. Crohn’s disease 
4. Acute granulomatous pneumonia 
5. Hepatic granulomatosis in chronic dialysis 
6. Talc granulomatosis 
7. Silicone granulomatosis 
8. BCG therapy 
9. 8-Cl-cAMP therapy 
10. Lipoid pneumonia 
11. Subcutaneous fat necrosis of the newborn 

**Rare presentations of the milk-alkali( calcium alkali) syndrome
1. Oyster shell calcium in betel nut chewing 
2. Overdose with buffered aspirin 
3. Massive cheese ingestion ( tofu perhaps as well)?
4. Munchausen’s syndrome 

**Unusual PTHrP-mediated hypercalcemic conditions
1. SLE 
2. HIV-associated lymphadenopathy 
3. Lymphedema of chest and pleural cavities 
4. Massive mammary hyperplasia during pregnancy 
5. During late pregnancy and lactation in hypoparathyroidism
6. With benign tumors of ovary and kidney, and in benign pheochromocytoma

** Medications that have been unusually associated with hypercalcemia
1. Omeprazole in acute interstitial nephritis 
2. Theophylline toxicity 
3. GH in intensive care unit patients 
4. Parenteral nutrition 
5. Foscarnet 
6. Hepatitis B vaccination 
7. 8-Cl-cAMP chemotherapy 
8. Manganese toxicity 

**Rare causes of hypercalcemia in which the mechanism is not known
1. Eosinophilic granuloma 
2. Leprosy in rheumatoid arthritis 
3. Mycobacterium avium complicating AIDS 
4. Cytomegalic virus infection in AIDS
5. Chronic berylliosis 
6. Nocardia asteroides pericarditis 
7. Diffuse octeoclastosis 
8. Paraffin granulomatosis 
9. Brucellosis 
10. Isolated ACTH deficiency 
11. Glucocorticoid withdrawal 
12. Hypocaloric diet in hypoparathyroidism 
13. Advanced chronic liver disease 
14. Type I Gaucher’s disease with acute pneumonia 
15. Lymphedema in SLE 
16. Juvenile rheumatoid arthritis 
17. Lymphadenopathy with high IL-6 

**Causes of Pseudohypercalcemia
1. High serum albumin 
2. Thrombocythemia 
3. Calcium binding to M-proteins 


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