Type I acquired cutis laxa: Report of a unique progressive case and short review.

Cutis laxa is a rare connective tissue disorder, characterized by a reduced number and abnormal properties of elastic fibers throughout the dermis, creating a clinical appearance of premature aging. It can be subdivided into inherited and acquired, the latter rarer than the former, and skin involvement may be localized or generalized. The etiology of acquired cutis laxa (ACL) remains unknown and there is no definitive treatment. We present the case of a 30-year-old man diagnosed with type I ACL with progressive systemic involvement at the renal, pulmonary, and digestive levels. Histological analysis of the skin revealed reduction and fragmentation of elastic fibers. Immunosuppressive treatment was started with prednisone, cyclophosphamide, and rituximab, with which a complete response to proteinuria was achieved and the progression of lung damage was limited. Autoimmune, infectious, and neoplastic diseases were ruled out.

Transformation of a myelodysplastic syndrome to acute myeloid leukemia and concurrent necrotizing sweet syndrome.

The Sweet's syndrome, is an inflammatory skin disorder characterized by extensive infiltration of neutrophils in the dermis with extension to the subcutis, known as acute febrile neutrophilic dermatosis. It may occur as a paraneoplastic syndrome. To our knowledge, there are currently few reports about transformation of a myelodysplastic syndrome to acute myeloid leukemia and concurrent necrotizing Sweet syndrome in the literature. Herein we describe an unusual case in a young patient with these characteristics that evolved to a fatal outcome.

Circumscribed storiform collagenoma, an unusual tumor.

Circumscribed storiform collagenoma is a rare benign tumor. It appears as an isolated skin lesion or as part of the clinical spectrum of Cowden syndrome. The pathogenesis is still controversial. Although its clinical expression is heterogeneous, it has a characteristic histological pattern. We describe a case of a solitary circumscribed storiform collagenoma not associated with Cowden syndrome.

Langerhans Cell Histiocytosis with Isolated Cutaneous Involvement Refractory to Polychemotherapy: A Case Report.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a neoplasm of the monocyte-macrophage lineage, characterized by clonal proliferation and dissemination of cells that express CD1a+ and CD207. It is a disorder that predominates in childhood. Although the skin is the second most frequently affected organ (30-60%), isolated cutaneous involvement is rare; its frequency does not exceed 4 to 12 percent of cases. Single system-LCH usually has a good prognosis. We describe a case of LCH with isolated cutaneous involvement that presented in an adult patient and was refractory to polychemotherapy.

[Coexistence of mycosis fungoides and essential thrombocythemia with JAK2V617F]. / Coexistencia de micosis fungoides y trombocitemia esencial con mutación JAK2V617F.

BACKGROUND: The coexistence of myeloproliferative neoplasms (MPNs), specifically essential thrombocythemia and lymphoproliferative neoplasms, are a very rare finding with a frequency < 1%. CASE REPORT: We present the case of a woman with diagnosis of mycosis fungoides early stage IB, of 5 months of evolution, she received systemic treatment based on methotrexate orally for 4 months; after this, she started with important thrombocythemia reaching up to 1 200 000/mm3 platelets and leukocytosis ranging from 10 000 - 13000/mL. A study protocol for chronic myeloproliferative disease was performed, reporting 90% cellular bone biopsy, erythroid myeloid ratio 5:1, 25 megakaryocytes per mm3, some with hyperlobed nuclei, and giant nuclei. Karyotype: 46XX. PCR without expression of BCR/ABL. JAK 2 positive. The diagnosis of essential thrombocythemia was concluded. CONCLUSIONS: There are several hypotheses seeking to elucidate the etiopathogenesis of the coexistence of myeloproliferative and lymphoproliferative neoplasms, some claim that they are precursors of the same multipotential stem cell, while others support that they are the result of a coincidence. More molecular studies are required to elucidate this unknown.

INTRODUCCIÓN: la coexistencia de neoplasias mieloproliferativas (NMPs), específicamente la trombocitemia esencial y las neoplasias linfoproliferativas, son un hallazgo muy raro, con una frecuencia menor al 1%. CASO CLÍNICO: presentamos el caso de una mujer con diagnóstico de micosis fungoides en etapa temprana IB de 5 meses de evolución, recibió tratamiento sistémico a base de metotrexate vía oral por 4 meses; posteriormente, inicia con trombocitemia importante llegando hasta 1 200 000/mm3 plaquetas y leucocitosis oscilando entre 10 000 - 13 000/mL. Se realizó protocolo de estudio para enfermedad mieloproliferativa crónica, en la biopsia de hueso se encontró celularidad del 90%, relación mieloide eritroide 5:1, megacariocitos 25 por mm3, algunos con núcleos hiperlobulados y núcleos gigantes. Del estudio de cariotipo se detectó 46XX y la prueba de reacción en cadena de la polimerasa (PCR) no detectó expresión de BCR/ABL. JAK 2 positivo. Se concluyó con diagnóstico de trombocitemia esencial. CONCLUSIÓN: existen varias hipótesis que buscan dilucidar la etiopatogenia de la coexistencia de neoplasias mieloides y linfoides a la vez; unas sostienen que son precursoras de la misma célula madre multipotencial, mientras que otras comentan ser resultado de una coincidencia. Se requieren de más estudios a nivel molecular para dilucidar esta incógnita.