Calcinosis cutis

Introduction

Calcinosis includes a wide range of disorders, which result in deposition of calcium and phosphate in an organic matrix of soft tissues. It commonly occurs in skin (calcinosis cutis), subcutaneous tissue and muscles and can involve visceral organs. The cause can be identified in most of the circumstances by clinical evaluation and investigations. But in some cases the etiology cannot be found out even after extensive work up.[2] We report one such case of idiopathic cutis.

Case Re-port

A 22-year-old male patient came with history of swellings over both elbows and knees and a sinus over right elbow discharging chalkly white material of 3 years duration. There had been similar swellings over left gluteal region and right elbow in the past about 4-years ago which had resolved on excision.

On examination, the swelling over right elbow was 5 cm. in diameter with a sinus discharging chalkly white material. There was a car on the medial aspect of the elbow. There were similar swellings over the left elbow and both the knees. Systemic examination was normal.

Investigations revealed normal complete haemogram, blood sugar, liver function and kidney function tests. Serum calcium and phosphate done on two different occasions were within normal limits. Serum uric acid, electrolytes and alkaline phosphatase were normal. 24 hour urinary calcium and phosphate excretions were normal. Serum parathyroid hormone level was normal. X--rays of elbows and knees showed no joint involvement and ultrasound examination of abdomen was normal. X-ray of skull was normal.

Skin biopsy demonstrated deposition of homogenous material in the dermis suggestive of calcium deposition.

Discussion

Deposition of calcium and phosphates in tissues is called calcification or calcinosis. If it gets organized as in bone formation, it is called ossification. Calcinosis is commonly seen as a consequence of connective tissue disorders or metabolic abnormalities.[2] But it can occur without any tissue injury or metabolic abnormalities. The three main types are:

1. Dystrophic-associated with connective tissue disorders due to tissue change. Eg. Dermatomyo-sitis, pseudoxanthoma elasticum or Ehlers Danlos syndrom 2.ldiopathic-not associated with any tis-sue change or damage. Eg. Calcinosis universalis, circumscripta ortumoral calcinosis. 3. Metastatic-associated with abnormal calcium and phospho-rus metabolism as in hypercalcemia or hyperphosphatemia. In this type visceral organs are more affected than the skin.

In this case there was no evidence of connective tissue disorders known to cause dystrophic calcification. Abnormal mineral metabolism was ruled out by investigations so metastatic calcinosis was not present. Skin biopsy showed calcium deposition in dermis and subcutis without evidence of tissue necrosis. Hence the case was concluded as idiopathic calcinosis cutis and reported for the interesting and uncommon presentation.