histologically , aggregates of calcium can be shown with von kossa stain.scn is a special type belonging to the idiopathic group , usually presenting as a solitary firm nodule on the head and neck.the pathogenesis of scn is not understood , yet . scn is a special type belonging to the idiopathic group , usually presenting as a solitary firm nodule on the head and neck . calcinosis cutis is a term used to describe a group of disorders in which calcium deposits form in the skin . , it has a profound effect on keratinocyte proliferation , differentiation , and cell - to - cell adhesion . cutaneous calcium deposits were describe first in 1877 , but it was in 1952 that winer described congenital nodular calcifications , currently known as scn . synonyms include winer 's nodular calcinosis , solitary genital nodular calcification , cutaneous calculi , and solitary congenital calcified nodule . the etiology of calcinosis cutis may be idiopathic or due to abnormal calcium or phosphorus metabolism of dermal collagen . scn is a rare form of idiopathic calcinosis ( ic ) that occurs more commonly in children , particularly in the head - and - neck region . scn can be present at birth without any previous history of cutaneous and systemic pathology or disturbances in the metabolism of calcium and phosphorus , with a male - to - female ratio of 2/1 . most lesions appeared as solitary , raised , tan , or white nodules on the upper eyelid or medial canthal skin of healthy , young patients . all reported patients with scn had normal serum levels of calcium and phosphates , with no other systemic abnormality or disseminated integumentary deposits . by contrast , additional calcium deposits beyond the eyelid warrant attention to the patient 's health status , as hyper - calcemic states have been reported to associate with eyelid margin , corneal , limbal , and inter - palpebral calcific deposit . the scn cases , which have been reported in the literature , are usually in the form of case reports in children with placement of the eyelid [ table 1 ] . to date published the cases we report a case of a 22-year - old man with multiple nodules of the bilateral dorsum of hands mimicking eruptive xanthoma with the review of the literature . a 22-year - old healthy white man presented with asymptomatic , multiple nodules on the bilateral dorsum of hands since he was 10 years old . clinical examination was remarkable for 13 lesions ( range in diameter 0.2 - 1 cm ) , white to yellowish , hard , non - sensitive nodules on the bilateral dorsum of hands [ figure 1 ] . the case was misdiagnosed as verruca vulgaris and was treated with cryotherapy at different centers . histopathology showed homogeneous basophilic masses and granules in the upper dermis , which were surrounded by foreign body reaction and epidermal hyperplasia , an appearance consistent with cutaneous calcinosis [ figure 2 ] . the lesions on the dorsum of righthand the histopathological image routine laboratory tests and metabolic evaluations ( calcium , phosphate , and parathyroid hormone ) , hematological parameters , and blood sedimentation rate were within normal limits . x - ray of the affected hands showed small radio - opaque focuses , but the bony structure did not show any pathology . the cause and histogenesis of these deposits have not been fully established , but several theories have been proposed . the most favored theory has been proposed by steigleder who believed that the calcium was deposited on a pre - existing lesion such as a hamartoma or nevus . cutaneous calcification may be divided into four major categories such as metastatic , dystrophic , idiopathic , and iatrogenic . metastatic calcinosis ( mc ) occurs in the presence of primary disorders of calcium / phosphate metabolism as well as from secondary causes such as hyper - parathyroidism , hyper - vitaminosis d , sarcoidosis , neoplastic involvement of bone , renal insufficiency , and milky alkali syndrome . metastatic calcification can occur in the media layer of the blood vessels and this may result in vascular occlusion . dystrophic calcification ( dc ) is the most common type of calcinosis cutis and occurs in the presence of normal serum levels of calcium and phosphates but in previously diseased skin . the dc that occurs in conjunction with the above entities does not likely involve a bacterial etiology . dc is common in childhood in the presence of such diseases as dermatomyositis , systemic scleroderma , crest ( calcinosis , raynaud phenomenon , esophageal dysmotility , sclerodactyly , and telangiectasia ) syndrome , morphea , subcutaneous fat necrosis of the newborn , and cutaneous neoplasms . iatrogenic calcinosis is a result of extravasation of some intravenous liquids such as calcium gluconate , calcium chloride solutions , during intravenous application , forming nodules in the skin . ic appears without an underlying cutaneous disease ; the clinical picture resembles the one seen in dc . lesions are usually seen in young and middle - aged men , presenting as asymptomatic round yellow multiple papules , ranging from a few millimeters to centimeters . ic occurs in the absence of evident tissue or metabolic abnormalities , and is further subdivided into three distinctive disorders of childhood : calcinosis circumscripta , ic of the scrotum , and scn . there is also a  milia - like  form that occurs on the hands , and face , of some patients with down syndrome . the milia - like calcinosis cutis lesions are mostly multiple especially seen on hands , feet , knees , and elbows to be more widely distributed . reported 21 cases of scn showing a male predominance with a male - to - female ratio of 2:1 . alper et al . presented a case where the lesion was localized on the knees of a 23-year - old female patient . the oral cavity is very rarely affected by calcinosis cutis of any type [ table 1 ] . histopathologically , scn is characterized by an intensely basophilic sub - epithelial calcium deposit beneath the acanthotic and papillomatous epidermis on hematoxylin and eosin - stained preparations . the deposits stain with von kossa 's stain for calcium and are surrounded by foreign body reactions , and trans - epidermal eliminations of calcium granules can be observed . the clinical diagnosis of scn is not easy and it is most often mistaken for verruca , molluscum contagiosum , pilomatricoma , epidermal cyst , milium , syringoma , congenital inclusion cyst , sebaceous cyst , or xanthoma . in our case , the diagnosis was made by histopathology , rather than the clinic . intra - lesional steroid injection and co2 laser have also have been used as alternative treatment modalities . eruptive xanthoma is in clusters throughout the body in the yellow - orange - colored papular lesions that are often surrounded by an erythematous halo . they appear in crops on the buttocks , extensor surfaces of the extremities , and flexural creases . in our case , yellow - white colored papules on the bilateral dorsum of the hands composed of a large number of settlers is similar to eruptive xanthoma . we considered cutaneous eruptive xanthomas in the differential diagnosis , which are characteristic lesions of hyper - lipidemia and chylomicronemia . rarely , eruptive xanthomas have been reported with hypo - thyroidism , nephrotic syndrome , and von gierke 's glycogen storage disease . rarely , these lesions may present with prominent leukocytoclasis as seen in papular neutrophilic xanthomas , which have been described in hiv - positive and immunocompromised patients . aldabagh and bergfeld described a patient with eruptive neutrophilic xanthomas with neither hyper - lipidemia nor immunocompromise . histologically , foamy macrophages are present in the dermis with an inflammatory infiltrate of lymphocytes and neutrophils . tendon xanthomatosis often accompanies familial hyper - cholesterolemia , but it can also occur in other pathological states . lesions of our case were not his tendons and our patient 's lipid profile was normal . our patient 's serum calcium and phosphorus levels were normal and there was no history of parenteral treatment . patient 's current physical examination , laboratory , and histopathological findings led us to the diagnosis of ic of the subcutaneous calcified nodule . for treatment of multiple lesions , the patient is advised to have follow - up examinations . scn , settled in the form of yellow - white - colored lesions , may be multiple and at atypical localization . clinicians should be aware that calcinosis cutis may involve the bilateral dorsum of hands and elicits appropriate history to exclude metastatic cutaneous calcification . dermatologists should include this entity in the differential diagnosis of multiple papular lesions on bilateral hand dorsums . sub - epidermal calcified nodules ( scns ) can rarely present with multiple nodules resembling xanthoma.although the head - and - neck region is the common location , unusual presentations on the dorsum of hands can occur . sub - epidermal calcified nodules ( scns ) can rarely present with multiple nodules resembling xanthoma . although the head - and - neck region is the common location , unusual presentations on the dorsum of hands can occur .