calcinosis cutis is subdivided into four types , namely metastatic , dystrophic , idiopathic and subepidermal calcinosis . according to this classification calcinosis associated with the injection of a calcium chloride preparation was recently described as iatrogenic calcinosis . recently , we encountered a similar case , and discuss here the relationship between the route of administration and the site of calcium deposition . the medical history included bladder cancer diagnosed 10 weeks earlier , which was resected surgically . was treated intraoperatively by common iliac artery bypass and intravenous infusion of 2% calcium chloride into the arm vein to induce vasoconstriction . postoperatively , no extravasation of the injected preparation was noted on the arm , but a red flare appeared around the area of administration . the patient was referred to the department of dermatology at postoperative week 7 for further management . physical examination showed an indurated plaque of 13  65 mm with linearly distributed ulcers covered by yellowish - white material , and the entire lesion was surrounded by reddish skin ( fig . 1 ) . laboratory data showed bun 25.2 mg / dl ( normal : 7.022.0 ) , serum creatinine 0.97 mg / dl ( normal : 0.30.8 ) , serum calcium 9.3 mg / dl ( normal : 8.010.5 ) , serum phosphate 4.4 mg / dl ( normal : 4.06.0 ) , and high sensitivity - parathyroid hormone 460 pg / ml ( normal : 160520 ) . the histopathological findings were similar in the two specimens and included deposition of basophilic amorphous substance in the upper and middle dermis ( fig . the amorphous material was eliminated transepithelially , with partial defect of the epidermis and substitution with crust . 2c ) . based on the above clinical and histopathological findings , the final diagnosis was calcinosis cutis . the whitish chalky substance disappeared gradually within 1 month , together with healing of the ulcers within 2 months , with scar formation ( fig . a search of the japanese literature published between 1990 and 2012 identified 18 cases of calcinosis cutis after administration of calcium preparations ( table 1 ) [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ] . the data included in table 1 are sorted according to the presence / absence of extravasation and the depth of the lesion . in the 3 biopsied cases out of 7 without extravasation , the deposition was confined to the dermis [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ] . in comparison , biopsies were obtained from 6 out of 10 cases with extravasation and the deposition was confined to the dermis in 4 out of 6 cases , although the extravasation should occur in the subcutis . therefore , direct deposition is not the reason of calcinosis in the dermis . several recent case argued that calcinosis cutis represents intravascular or vascular wall deposition , which is triggered by endothelial failure or obstruction by catheter tip misplacement , in the presence of local hypercalcemia near the catheter . in their opinion , it is a secondary extravasation due to vascular occlusion . however , the lesion in the 3 cases without extravasation , including our case , was confined to the dermis , i.e. , lack of involvement of subcutaneous vessels and no use of catheters . since there is no discussion of this feature , we hypothesize that the pathomechanism of calcinosis cutis is as follows : introduction of the needle causes tissue injury , which causes capillary disruption in the dermis ( fig . 4b ) , leading to a transient increase in calcium concentration in the extracellular matrix between collagen fibers , with subsequent binding of calcium to phosphate in the dermis ( fig . 4c ) and deposition of calcium phosphate crystals in the dermis .
a 61-year - old female received intravenous injection of calcium chloride after common iliac artery bypass surgery . 
 a red flare appeared at the site of the intravenous infusion on the left forearm and gradually progressed to induration . 
 seven weeks later , she was referred to the department of dermatology for management . 
 physical examination showed an indurated plaque measuring 13  65 mm in size , with linearly distributed ulcers covered by yellowish - white substance , surrounded by reddish skin . 
 laboratory tests showed no significant abnormalities including serum calcium , phosphate and thyroid hormones . 
 cultures were negative for microorganisms . 
 histopathological examination showed calcium deposition confined to the dermis . 
 the lesion healed spontaneously within 2 months with scar formation . a review of the japanese literature showed confinement of calcium deposits to the dermis in most of the reported cases . 
 we speculate that the pathomechanism of dermal calcinosis includes needle - induced tissue injury with capillary destruction , leading to release of excess calcium between collagen fibers , and its binding to phosphate in the dermis and deposition as calcium phosphate crystals .