[Primary systemic amyloidosis presenting as polymyalgia rheumatica and giant cell arteritis]. / Forma de presentación de una amiloidosis primaria como polimialgia reumática y arteritis de células gigantes.

Primary systemic amyloidosis or AL-amyloidosis is an uncommon disease characterized by the accumulation in vital organs of a fibrillar protein consisting of monoclonal light chains. It is a plasma-cell dyscrasia related to multiple myeloma where clonal plasma cells in the bone marrow produce immunoglobulins that are amyloidogenic. A monoclonal component is present in the serum or urine of 90% of patients. The presentation of most patients with AL amyloidosis is usually related to congestive heart failure, nephrotic syndrome o peripheral neuropathy, but there are unusual features suggesting giant cell arteritis (GCA) and polymyalgia rheumatic (PMR). Although in the majority of AL cases the plasma cells clone is small, the assumption is that the outcome of the disease is uniformly fatal (median survival 12-15 months) and treatment is analogous to those used in malignant proliferative disease. We describe a patient with AL amyloidosis who presented with manifestations of GCA and PMR, and we review the main characteristics of primary amyloidosis.

Forma de presentación de una amiloidosis primaria como polimialgia reumática y arteritis de células gigantes / Primary systemic amyloidosis presenting as polymialgia rheumatica and giant cell arteritis

La amiloidosis primaria o amiloidosis AL es una discrasia de células plasmáticas difícil de diferenciar del mieloma múltiple, que se caracteriza por el depósito de una proteína fibrilar de cadenas ligeras monoclonales en tejidos y órganos. Es una enfermedad poco frecuente, en la que un clon de células plasmáticas en la médula ósea produce inmunoglobulinas amiloidogénicas. En el 90 por ciento de los casos se detecta por inmunoelectroforesis inmunoglobulinas monoclonales en sangre u orina. Habitualmente se manifiesta como insuficiencia cardiaca, síndrome nefrótico o neuropatía periférica, pero excepcionalmente pueden existir síntomas sugestivos de arteritis de células gigantes (ACG) o polimialgia reumática (PMR). Aunque el número de clones de células plasmáticas en la médula ósea suele ser pequeño, la actitud terapeútica es la de una enfermedad proliferativa maligna, siendo la supervivencia media de 12 a 15 meses.Presentamos un paciente cuya primera manifestación de amiloidosis primaria fueron síntomas de ACG y PMR, y revisamos las principales características de esta enfermedad. (AU)

[Monoclonal component in visceral leishmaniasis: a rare association that can lead to misdiagnosis]. / Componente monoclonal en leishmaniasis visceral: rara asociación que puede conducir a un falso diagnóstico.

The detection of monoclonal components is exceptional in patients with visceral leishmaniasis (VL). The cases are here reported of two patients with VL in a non-endemic area and monoclonal components which posed problems for the differential diagnosis with other entities associated with the presence of paraproteins. The predominant clinical manifestations in both cases were general symptoms, fever and severe spleen enlargement. One patient had a monoclonal triple band in urine and the other several oligoclonal bands in serum. In the initial bone marrow aspiration smear no parasites were observed in any of the two cases but a remarkable plasmacytosis in one of them. The presence of increased serum titers of anti-Leishmania antibodies was the first demonstrative finding of VL. The diagnosis was confirmed with positive culture of Leishmania and therapy with pentavalent antimonials was successful in both cases. The different diagnostic possibilities are discussed and the possibility of VL is emphasized even in non-endemic areas when monoclonal components in serum or urine specimens are found and consistent clinical findings are present.