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L Perrin

Publications and source records attributed to L Perrin.

11 recordsLinked to original sources

Epidemiology of vertically transmitted HIV-1 infection in Switzerland: results of a nationwide prospective study. Swiss Neonatal HIV Study Group.

A nationwide study involving 286 children of human immunodeficiency virus (HIV)-infected mothers living in Switzerland has been performed with the participation of all paediatricians interested in HIV infection in the country. Of these children 201 could be followed up prospectively from birth up to a median age of 22 months. Prevalence of HIV infection in Swiss parturients was estimated at 0.1% and apparently remained stable from 1986 to 1989. Vertical transmission rate was estimated at 14%-20%. Variables of maternal or perinatal history were not associated with transmission rate. Transmission to pairs of siblings of the same mothers was discordant in 33% (6 of 18), with always the elder sibling being infected. Postneonatal mortality in infants of HIV-infected mothers followed up from birth was increased 15-fold over the general population with a very high incidence (2 in 100) of sudden infant death apparently unrelated to HIV infection.

Child

Toxoplasma encephalitis in patients with the acquired immunodeficiency syndrome.

Among 504 cases of AIDS diagnosed between 1983 and 1990, there were 86 patients (17%) with toxoplasma encephalitis (TE). All were symptomatic at the time of diagnosis. General signs such as fever, neck stiffness, or headache were present in 87.2%, and 75.6% had focal signs. The primary means of diagnosis was computerized tomographic scanning, revealing 169 lesions of which 80% were immediately contrast-enhancing. All patients had IgG antibodies against Toxoplasma gondii either before (74 of 75 evaluable patients) or at the time of diagnosis of TE (73 of 75). Elevated antibody titers were present in 44% of evaluable patients, compared to 11% of patients with AIDS and other opportunistic infections. Initial treatment was pyrimethamine plus sulfonamides in 65 patients, and pyrimethamine plus clindamycin in 12 patients, with other combinations or no treatment accounting for the remainder. Life-table analysis of the time to discontinuation of treatment because of suspected side effects suggested that sulfadiazine was significantly more toxic, with 48% of patients experiencing an interruption in treatment after 30 days, than pyrimethamine (12%) or clindamycin (24%). The 30-day mortality rate was 12%, and median survival was 310 days after diagnosis, 530 in patients treated with zidovudine and 190 days in those not so treated. Of 82 evaluable patients, 16 relapsed once and 4 of these more than once. The risk of relapse was 27% 1 year after diagnosis of a first episode of TE.

Acquired Immunodeficiency Syndrome

Hepatitis C: a possible etiology for cryoglobulinaemia type II.

Out of 15 successive patients with mixed essential cryoglobulinaemia type II (monoclonal IgM kappa/IgG), 13 had serological evidence for hepatitis C infection as shown by specific enzyme immunoassays and immunoblot. RNA was purified from the serum of seven patients and hepatitis C sequences were identified in five following reverse transcription and DNA amplification. The liver histology showed chronic active hepatitis with or without cirrhosis in the 12 patients with hepatitis C who had a liver biopsy. The two patients without serological evidence of hepatitis C suffered from haematological malignancies. Hepatitis C may be a major etiological agent of cryoglobulinaemia type II.

Adult

[HTLV-I/II in Switzerland: apropos of 4 case reports].

HTLV-I/II (human T-cell lymphotropic virus type I and II) infection is endemic in South Japan, Subsaharan Africa, the Caribbean and in regions of South America and of the United States. The infection almost always remains asymptomatic but is also associated with two distinct diseases: tropical spastic paraparesis (TSP), and adult T-cell leukemia (ATL). Although very rare in Europe, HTLV-I/II infection may occur in patients originating from endemic areas. We report the cases of four patients seropositive for HTLV-I/II, all of them living in Switzerland. Three of them originate from Zaire; the fourth is a Swiss female married to a Taiwanese. One patient has TSP; one has pyramidal signs along with systemic vasculitis-associated neuropathy; the third is HIV-position with stage III B infection, without symptoms of TSP or ATL; the last is entirely asymptomatic.

Adult

Epidemiological basis for clinical diagnosis of childhood malaria in endemic zone in West Africa.

It is difficult to distinguish childhood malaria from other common febrile disorders by parasite count alone, because of the wide variation in tolerance of parasitaemia among individuals. We postulated that the proportion of febrile episodes among young children that can be attributed to parasitaemia varies according to simple clinical criteria. We studied 1114 children aged 2-9 years, who attended a dispensary in the Republic of Niger, with a case-control approach; each of 557 febrile children was matched with a non-febrile control by sex, age, ethnic group, and day of presentation. Febrile episodes were classified according to three clinical criteria: the presence of a likely non-malarial cause; the duration (less than 3 or more than 3 days before presentation); and the intensity (below 39 degrees C or 39 degrees C and above). There was no evidence for an association between febrile episodes and parasite count during the dry, low-transmission, season. During the rainy, high-transmission, season, by contrast, there was a highly significant relation (p less than 0.0001) between the likelihood of fever and the parasite count; each clinical criterion strengthened the association. There was no association between parasitaemia and low intensity fevers, with an obvious cause, that started 3 or more days before presentation, even in the rainy season; however, the relative risk of a fever that met all three criteria developing in those with vs those without parasitaemia was 27.5. The proportion of febrile cases attributable to detectable parasitaemia (population attributable risk) ranged from 0 to 0.92. Our results suggest that simple clinical criteria may be valuable in the selection of febrile patients for antimalarial treatment. In this geographic area, high fever of short duration and with no other obvious cause that occurs during the rainy season is most likely to be malaria.

Animals

Bullous pemphigoid autoantibodies, HIV-1 infection and pruritic papular eruption.

Bullous pemphigoid (BP)-type autoantibodies were found by Western blot (WB) analysis of epidermal extracts in the serum of 38% of HIV-seropositive patients compared with 21% of HIV-seronegative patients with chronic pruritus and 76% of patients with BP. They were further identified as BP autoantibodies (BPab) by immunoprecipitation and immunoelectron microscopy. Their incidence increased from 21% in HIV infection stage II to 37% and 43% in stages III and IV, respectively. Of the patients suffering from HIV-related chronic pruritic papulovesicular eruption. 75% showed circulating BPab as compared with 29% in those without skin problems (P = 0.0066) and, among them, 30% met the diagnostic criteria for BP when histology, WB, immunofluorescence and immunoelectron microscopy techniques were used. In conclusion, this study identifies an autoimmune skin reaction that may account for, or be related to, the distressing pruritic eruptions occurring in HIV-infected patients.

Adult

Human T cell activation. Synergy between CD73 (ecto-5'-nucleotidase) and signals delivered through CD3 and CD2 molecules.

Interaction of the glycosyl phosphatidylinositol-linked differentiation Ag CD73 (ecto-5'-nucleotidase) with the CD73-specific mAb 1E9 generates agonistic signals that strongly synergize with T cell activation induced by CD3 and CD2 mAb. This synergy is observed only when 1E9 is immobilized on plastic and occurs in the absence of accessory cells or exogenous lymphokines. 1E9 induces a rapid (though transient) increase in [Ca2+]i in a minor proportion (20 to 30%) of unfractionated T lymphocytes (presumably CD73+ cells). However, this [Ca2+]i mobilization is not sufficient to fully activate CD73+ T cells, as shown by the requirement of additional signals such as CD3 or CD2 stimulation to initiate T cell proliferation. These signals cannot be substituted by the exogenous lymphokines, rIL-1, rIL-2, or rIL-4, or PMA (when T cells are rigorously depleted of monocytes). These data indicate that CD73 may behave as an accessory molecule regulating interactions between T cells and antigens or APC. A comparison was carried out with mAb 9.3 to the differentiation Ag CD28, another agonistic molecule with activating properties similar to CD73. Despite their lower percentage, the ability of CD73+ T cells to amplify the proliferation induced by CD3 or CD2 mAb was equivalent or even greater than that of CD28+ T cells. Once activated, CD73+ cells may recruit the remaining (CD73-) cells primed by CD3 or CD2 stimulation. Based on these data, we suggest that CD73+ T lymphocytes may be a specialized subset to amplify immune responses originated by the CD3 and CD2 activation pathways. Finally, the functional association between CD73 and integral membrane molecules like CD3 and CD2 suggests that GPI-anchored molecules may play a role in transmembrane signaling mediated by conventional second messenger systems.

5'-Nucleotidase

Loss of antibodies against hepatitis C virus in HIV-seropositive intravenous drug users.

A time-point survey of 262 ex-intravenous drug users (IVDUs) on methadone treatment showed serological evidence of hepatitis C virus (HCV) in 64%, hepatitis B virus in 74% and HIV in 36%. Analysis of previously collected frozen stored sera of the same patients showed that 31 further IVDUs had had anti-HCV antibodies in the past and had lost them in a time-dependent fashion. Most HCV seroreversion was detected in HIV-positive people: 20 out of 85 in the HIV-positive group versus 11 out of 18 in the HIV-negative group.

Adult

[50 submandibular gland resections (author's transl)].

The authors review the etiological, and therapeutic data obtained from a statistical study of a homogenous group of 50 patients after submandibular gland resections. The operation was conducted for calculi in the gland in 56% of cases, infections in 24% and for other causes in the few remaining cases, including 4% with glandular tumors. From the technical point of view, the two cutaneous approaches with section of the vessels and simple enucleation were able to be employed in 76% and 24% of the cases respectively; the ease with which cleavage was obtained being the main factor whatever the etiology. Wharton's duct must be systematically and completely removed when calculi are present. The indications for therapy can be summarized as follows: -- systematic operation on any suspicious tumor for which the etiology is not rapidly discovered, -- determining factors for operation are also infections, recurrences, and a posterior localization of the calculi, -- postoperative complications are minor and consist mainly of paresis of the VIIth cranial nerve, which always regressed in this series.

Adult

[Pseudothrombopenia (proceedings)].

Two cases of spurious thrombocytopenia are reported, one induced by platelet satellitism and the other by platelet aggregation. These phenomena occur in vitro, only in the presence of EDTA and are linked with the presence of IgG in the patients' sera.

Aged