Differences in gamma interferon production in vitro predict the pace of the in vivo response to Leishmania amazonensis in healthy volunteers

The initial encounter of Leishmania cells and cells from the immune system is fundamentally important in the outcome of infection and determines disease development or resistance. We evaluated the anti-Leishmania amazonensis response of naive volunteers by using an in vitro priming (IVP) system and comparing the responses following in vivo vaccination against the same parasite. In vitro stimulation allowed us to distinguish two groups of individuals, those who produced small amounts of gamma interferon (IFN-gamma) (n = 16) (low producers) and those who produced large amounts of this cytokine (n = 16) (high producers). IFN-gamma production was proportional to tumor necrosis factor alpha and interleukin 10 (IL-10) levels but did not correlate with IL-5 production. Volunteers who produced small amounts of IFN-gamma in vitro remained low producers 40 days after vaccination, whereas high producers exhibited increased IFN-gamma production. However, 6 months after vaccination, all individuals tested produced similarly high levels of IFN-gamma upon stimulation of their peripheral blood mononuclear cells with Leishmania promastigotes, indicating that low in vitro producers respond slowly in vivo to vaccination. In high IFN-gamma producers there was an increased frequency of activated CD8(+) T cells both in vitro and in vivo compared to the frequency in low producers, and such cells were positive for IFN-gamma as determined by intracellular staining. Such findings suggest that IVP responses can be used to predict the pace of postvaccination responses of test volunteers. Although all vaccinated individuals eventually have a potent anti-Leishmania cell-mediated immunity (CMI) response, a delay in mounting the CMI response may influence resistance against leishmaniasis.

Involvement of the central nervous system in dengue fever: three serologically confirmed cases from Fortaleza Ceará, Brazil

Three cases of dengue fever involving the central nervous system (CNS) are reported. All occurred in 1994 during a dengue (DEN) epidemic caused by serotypes DEN-1 and DEN-2. The first case examined was a 17-year-old girl who complained of fever, nuchal rigidity and genital bleeding. Three blood samples were positive by anti-dengue IgM ELISA and showed hemagglutination-inhibition (HI) test titers > or = 1,280. The second case concerned a 86-year-old women with fever, muscle and joint pains, altered consciousness, syncope, nuchal rigidity and meningismus. Her blood sample showed an HI titer of 1:320 for flaviviruses, and an IgM ELISA positive for dengue. The third case was a 67-year-old women with fever, abnormal behaviour, seizures, tremor of extremities, thrombocytopenia, increased hematocrit and leukopenia. The patient suffered a typical case of dengue hemorrhagic fever with ensuing shock and a fatal outcome. A single blood sample showed HI antibodies of > or = 1,280 and an IgM ELISA positive for dengue. No virus could be isolated from any patient by inoculation of blood into C6/36 cells and suckling mice. No other agent of disease was encountered in the patient.

Pulmonary function after cholecystectomy performed through Kocher's incision, a mini-incision, and laparoscopy

Comparative pulmonary function after cholecystectomy performed through Kocher's incision, a mini-incision, and laparoscopy was evaluated. Forty-five patients were randomly and prospectively divided into three groups of 15 each, depending on the surgical access employed. Forced vital capacity (FVC), forced expiratory volume at 1 second (FEV1), and forced expiratory flow at 25% to 75% (FEF25-75%) were determined 1 to 3 days before and 16 to 24 hours after cholecystectomy. The percent reduction of FVC (p = 0.0170), FEV1 (p = 0.0191), and FEF25-75% (p = 0.0045) was smaller after laparoscopic cholecystectomy than after Kocher's incision cholecystectomy. The percent reduction of FVC (p = 0.0170) was smaller after mini-incision cholecystectomy than after Kocher's incision cholecystectomy. There was no difference in the FEV1 (p = 0.0971) or FEF25-75% (p = 0.2058) between these two groups. FEF25-75% was significantly less impaired in the laparoscopic group than in the mini-incision group (p = 0.0327). No difference between these two groups was found in FVC (p = 0.5755) or FEV1 (p = 0.3952). It is concluded that postoperative pulmonary function is less impaired after laparoscopic cholecystectomy than after either mini-incision or Kocher's incision cholecystectomy.

Histoplasmosis in individuals with acquired immunodeficiency syndrome (AIDS): report of six cases with cutaneous-mucosal involvement

The authors report the first six cases of disseminated histoplasmosis and acquired immunodeficiency syndrome (AIDS) seen at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo, from 1987 to 1989, with emphasis on dermatological clinical manifestations, nasal mucosa lesions and treatment. The mycosis was the first manifestation of AIDS in four patients. It is concluded that biopsies of the lesions for histopathologic study and fungal culture are important for diagnosis.