Acquired reactive perforating collagenosis in dermatomyositis

Reactive perforating collagenosis and systemic lupus erythematosus: A rare case report

BACKGROUND

Transepidermal clearance of altered collagen and excessive excretion of keratin are characteristics of a rare cutaneous disorder known as reactive perforating collagenosis (RPC). There are different forms of RPC; however, the acquired form is the most prevalent and inherited. Reactive perforating collagenosis is rarely described in autoimmune rheumatic diseases; instead, it is typically linked to systemic conditions such as renal failure or hepatic disease.

METHODS

A 31-year-old Saudi female patient who was initially diagnosed with undifferentiated connective tissue disease. She developed RPC with a severe diffuse itchy skin rash with numerous papules and nodules with central hyperkeratotic plugs over the lower limb, upper limb, and face.

RESULTS

The patient tested positive for antinuclear antibody; however, a year later, patient developed Raynaud's phenomenon, oral and nasal ulcers, malar rash, fatigue, and lupus rash around her eyes, and systemic lupus erythematosus was diagnosed clinically. The patient was treated for reactive perforating collagenosis with systemic antihistamines (diphenhydramine 50 mg orally twice daily), topical steroid cream (betamethasone dipropionate cream), and oral isotretinoin (20 mg daily). The patient was advised to undergo phototherapy. A year later, she presented with symptoms of systemic lupus erythematosus and started taking oral hydroxychloroquine 200 mg twice daily for systemic lupus erythematosus. The patient is listed on follow-up.

CONCLUSION

Variable skin rash can mimic systemic lupus erythematosus and vasculitis. Therefore, reactive perforating collagenosis is a skin condition that requires high clinical suspension for diagnosis, and it might be challenging to determine whether it is an association or a complication. Furthermore, the timing of the skin biopsy may be crucial for the diagnosis of reactive perforating collagenosis.

Acquired reactive perforating collagenosis: A report of a typical case

BACKGROUND

Reactive perforating collagenosis (RPC) is a rare form of transepithelial elimination, in which altered collagen is extruded through the epidermis. There are 2 types of RPC, acquired RPC (ARPC) and inherited RPC, while the latter is extremely rare. Here we report on 1 case of ARPC.

METHODS

A 73-year-old female was presented with strongly itchy papules over her back and lower limbs for 3 months. She denied the history of oozing or vesiculation. A cutaneous examination showed diffusely distributed multiple well-defined keratotic papules, 4 to 10 mm in diameter, on the bilateral lower limbs and back as well as a few papules on her chest and forearm. Scratching scars were over the resolved lesions while Koebner phenomenon was negative. The patient had a history of type 2 diabetes for 15 years. Laboratory examinations showed elevated blood glucose level. Skin lesion biopsy showed a well-circumscribed area of necrosis filled with a keratotic plug. Parakeratotic cells and lymphocytic infiltration could be seen in the necrosed area. In dermis, sparse fiber bundles were seen perforating the epidermis. These degenerated fiber bundles were notarized as collagen fiber by elastic fiber stain, suggesting a diagnosis of RPC.

RESULTS

Then a diagnosis of ARPC was made according to the onset age and the history of diabetes mellitus. She was treated with topical application of corticosteroids twice a day and oral antihistamine once a day along with compound glycyrrhizin tablets 3 times a day. And the blood glucose was controlled in a satisfying range. Two months later, a significant improvement was seen in this patient.

CONCLUSION

Since there is no efficient therapy to RPC, moreover, ARPC is considered to be associated with some systemic diseases, the management of the coexisting disease is quite crucial. The patient in this case received a substantial improvement due to the control of blood glucose and application of compound glycyrrhizin tablets.

Acquired reactive perforating dermatosis

Acquired reactive perforating dermatosis is characterized by umbilicated erythematous papules and plaques with firmly adherent crusts. Histopathological examination shows a typical cup-shaped ulceration in the epidermis containing cellular debris and collagen. There is transepidermal elimination of degenerated material with basophilic collagen bundles. The etiology and pathogenesis of acquired reactive perforating dermatosis are unclear. Metabolic disorders and malignancies are associated with this dermatosis. Associated pruritus is regarded as a key pathogenic factor. Constant scratching may cause a repetitive trauma to the skin. This pathogenesis may involve a genetic predisposition. The trauma may lead to degeneration of the collagen bundles. Treatment of acquired reactive perforating dermatosis follows a multimodal approach. Apart from the treating any underlying disease, treatment of pruritus is a major goal. Systemic steroids and retinoids, as well as UVB phototherapy are well-established treatment options. Some patients may also benefit from oral allopurinol.