Rhabdomyomatous mesenchymal hamartoma resembling scleroderma ‘en coup de sabre’: a case report and literature review

Abstract

The rash in PEP typically begins in the abdominal striae with sparing of the umbilicus. Spreading to the trunk and extremities may occur over a period of days but the face, palms and soles are usually unaffected. The pruritic papules may coalesce to form urticated plaques. Subepidermal vesicle formation has been described in PEP, 5 but not frank bullae. The condition is most unlikely to recur 6 and is not associated with an adverse outcome for either the mother or the infant. 1,6 Treatment 7 involves reassurance of the mother of the benign nature of the condition and the use of topical, moderately potent steroids and soothing emollients. A short course of systemic steroids may be required for severe cases.The histology of the condition is relatively characteristic but not specific. Several other conditions can give similar histological appearances including PG, allergic contact dermatitis, and drug or arthropod reactions. Therefore clinicopathological correlation is essential. The clinical differential diagnosis of PEP includes viral exanthemas, drug eruption, erythema multiforme, urticaria, contact dermatitis and early PG. At the time of their onset PEP and PG may be difficult to distinguish on clinical and histological grounds. 7 The development of bullous lesions has previously been considered diagnostic of PG. However, apart from the development of bullous lesions, this case had all of the hallmarks of PEP. The two disorders can be confidently differentiated by direct immunofluorescence of perilesional skin which demonstrates complement deposition at the basement membrane zone in all cases of PG and is consistently negative in PEP. The absence of complement deposition at the basement membrane has been confirmed by immunoelectron microscopy. 8 Others have reported unusually florid cases of PEP with features that also raised the possibility of PG, such as the presence of vesicles, involvement of palms and soles and continuation of the rash into the postpartum period. 9 The development of frankly bullous lesions would, until now, have been regarded as indicative of PG. However, this patient demonstrates that bullous lesions can also occur in PEP. Therefore this case redefines our clinical criteria for the diagnosis of pregnancy eruptions and highlights the crucial role of immunofluorescence studies in their accurate diagnosis.

Rhabdomyomatous Mesenchymal Hamartoma of Nasal Vestibule

“…3,5 Rhabdomyomatous mesenchymal hamartoma usually presents as raised lesions such as pedunculated, sessile, papillomatous, or polypoid. 6,7 However, there is also a case of RMH presenting as depressed skin lesions. 6 It has been thought that RMH is derived from the aberrant migration of skeletal muscle fibers into the dermis during embryogenesis.…”

“…6,7 However, there is also a case of RMH presenting as depressed skin lesions. 6 It has been thought that RMH is derived from the aberrant migration of skeletal muscle fibers into the dermis during embryogenesis. 2 Therefore, RMH is usually considered as a congenital disease, and at least 70% of RMHs previously reported are present at birth.…”

Congenital Papule on the Anterior Neck

“…It has also been reported to occur in unusual sites, including the vagina , toe , oral cavity, nasal vestibule , and anal margin . Although typically a raised lesion, one case of a depressed skin lesion has been reported . RMH is usually asymptomatic.…”

Rhabdomyomatous mesenchymal hamartoma: a case report

“…Microscopically these lesions are constituted by striated muscle fibers randomly distributed, intermingled with mature adipose tissue, collagen bands, blood vessels, and elastic fibers (1,16) . Adnexal structures interwoven with the muscle bundles are reported.…”