[3, 8] In adults, this complication occurs essentially in immunocompromised[3, 6] or elderly (>65 years) patients.[5, 7] In immune-competent adults, Shigella bacteremias are quite uncommon and clinical presentations often mild,[4, 5, 7] suggesting possible underestimation. Clinically, Selleck Bortezomib the main symptom is a febrile, acute (<7 days), diarrhea frequently without blood, but often associated with dehydration. Sometimes, especially in immunodeficient adults, diarrhea can persist and become chronic; or diarrhea may be absent and a fever or sepsis may be the only symptom.[3, 6] However, patients of any age can be afebrile. Bacteremic symptoms can vary from mild, as in our two observations, to severe with subsequent
complications.[3, 6] Laboratory investigations generally reflect an inflammatory response, and do not predict bacteremia or fluid loss-induced circulatory instability. Leucopenia or thrombocytopenia can be seen. In HIV-infected
adults, CD4 counts are generally lower than 200/mm3, reflecting severe immunodeficiency. Diagnosis is based on blood cultures. The Shigella group includes four serogroups such as Shigella dysenteriae, S flexneri, Shigella boydii, and Shigella sonnei. S flexneri, the most frequently encountered species in endemic zones and travelers, CB-839 mw is mainly responsible for bacteraemia.[1-5] Of note, fecal cultures can be negative, as occurred in both of our cases, thus emphasizing the need for systematically obtaining blood cultures in all invasive diarrheas. Pathogenicity is similar for the four serogroups. Interactions between bacterial virulence factors and host immunity induce an inflammatory response which often limits the invasion of the colon mucous membrane. However, because of bacterial factors, eg, virulence, size of bacterial inoculum, or host factors such as young age or immunodeficiency, extra-intestinal
complications like bacteremia may occur.[1-3] Thus in nearly an immune-competent young adult, Shigella bacteremia is quite unusual, and reasons for its occurrence must be sought, eg, co-morbidities such as in our two patients. The first patient had taken a prolonged loperamide self-treatment and high dose ibuprofen, but no antibiotics. Loperamide delays bacterial clearance due to its inhibitive effect on smooth muscle structure,8 and has been associated with intestinal complications in travelers’ diarrheas. It should not be taken alone when an invasive pathogen is suspected, especially in a gross bloody or febrile (>38.5°C) diarrhea.[8, 10, 11] But its use in combination with an antimicrobial treatment was shown to be safe and shorten duration of diarrhea in adults with dysentery due to Shigella sp. Concomitant use of loperamide and ibuprofen but no antibiotics taking may have favored the occurrence of bacteremia. The second patient was co-infected with P falciparum. In the tropical environment, concomitant bacterial bloodstream infection with malaria is frequent.