ABSTRACT
A diarreia crônica, caracterizada pela presença de mais de três dejeções de consistência pastosa durante pelo menos quatro semanas, é frequentemente encontrada na prática clínica. Na diarreia crônica, a probabilidade de uma etiologia infecciosa é baixa, sendo as causas funcionais, inflamatórias, osmóticas ou secretórias mais comuns. A amebíase intestinal é uma causa de diarreia crônica, causada pelo protozoário Entamoeba histolytica, sendo comum e prevalente em países em desenvolvimento. Pode ter várias formas de apresentação, sendo na maioria dos casos assintomática. Apresenta-se o caso clínico de um paciente de 27 anos, sexo masculino, raça caucasiana, homem que pratica sexo com homens (HSH), com diarreia crônica com início há cerca de seis anos. O exame objetivo não revelava alterações. Realizou exame parasitológico de fezes, com isolamento de quistos de Entamoeba histolytica. Foi medicado com metronidazol e paromomicina com resolução clínica do quadro. É importante para o Médico de Família equacionar esta etiologia na investigação de pacientes com diarreia, para um correto e atempado diagnóstico e tratamento, de modo a evitar exames desnecessários, possíveis complicações, a transmissão do agente e um grave problema de saúde pública.
Chronic diarrhea, characterized by the presence of more than three loose stools for at least four weeks, is often found in clinical practice. In chronic diarrhea, the probability of an infectious etiology is low, having usually a functional, inflammatory, osmotic or secretory origin. Intestinal amebiasis is a cause of chronic diarrhea, caused by the protozoan Entamoeba histolytica, common and prevalent in developing countries. It can have different presentations but most patients are asymptomatic. We present a 27-year-old Caucasian male, man who have sex with men (MSM), with chronic diarrhea starting six years ago. The physical exam was normal. A parasitological stool examination was performed with isolation of cysts of Entamoeba histolytica. He was treated with metronidazole and paromomycin with clinical resolution. It is important for General Practice to address this etiology in the investigation of patients with diarrhea for a correct and timely diagnosis and treatment, to avoid unnecessary testing, possible complications, transmission of the agent and a serious public health problem.
La diarrea crónica, caracterizada por la presencia de más de tres heces de consistencia blanda durante al menos cuatro semanas, es frecuentemente encontrada en la práctica clínica. En la diarrea crónica, la probabilidad de una etiología infecciosa es baja, siendo las causas funcionales, inflamatorias, osmóticas o secretoras más comunes. La amebiasis intestinal es una causa de diarrea crónica, causada por el protozoario Entamoeba histolytica, siendo común y prevalente en los países en desarrollo. Puede tener varias formas de presentación, siendo en la mayoría de los casos asintomática. Presentamos un paciente de 27 años, sexo masculino, caucásico, hombre que tiene sexo con hombres (HSH), con diarrea crónica con inicio hace cerca de seis años. El examen objetivo no reveló alteraciones. Realizó un examen parasitológico de heces, con aislamiento de quistes de Entamoeba histolytica. Fue medicado con metronidazol y paromomicina con resolución clínica del cuadro. Es importante para el médico de familia considerar esta etiología en la investigación de pacientes con diarrea, para un correcto y oportuno diagnóstico y tratamiento, de modo a evitar, exámenes innecesarios, posibles complicaciones, la transmisión del agente y un grave problema de salud pública.
Subject(s)
Humans , Male , Adult , Public Health , Diarrhea , Dysentery, Amebic , Entamoeba histolyticaABSTRACT
This article presents a history of Entamoeba histolytica spanning since the remote times when it was not even recognized as a cause of human disease to the recent molecular advances. Feder Losch (1875) in Saint Petersburg, found amoebae in fecal samples but only regarded them as responsible for maintaining the inflammatory process, not as a cause of dysentery. Fritz Schaudinn (1903) established the differentiation between Entamoeba histolytica and Endamoeba coli, Schaudinn decided to call it E. histolytica because of its ability to cause tissue lysis. Emile Brumpt (1925) based on experimental studies, pointed out the existence ofE. Histolytica as a species complex, comprising two morphologically indistinguishable species, E. dysenteríae which is the cause of symptomatic infection, and Entamoeba dispar found only in asymptomatic carriers. Louis Diamond et al (1961) during the 1960s developed an axenic culture medium for E. histolytica which allowed in vivo and in vitro studies. Sargeaunt and Williams (1978) distinguished for the first time E. histolytica strains by isoenzyme electrophoresis, thus confirming thatE. hystolytica was indeed a species complex comprising both pathogenic and non-pathogenic species. William Petri et al (1987 demonstrated that the 170 kDa protein with greater antigenicity was the Gal/GalNac-specific lectin. Diamond and Clark (1993) described again Brumpt's original 1925hypothesis, concluding that there was enough evidence to support the existence of two morphologically indistinguishable species, a pathogenic and a nonpathogenic one, corresponding to E. histolytica and Entamoeba dispar respectively. The World Health Organization accepted this hypothesis in 1997.