Epidemiological data on Staphylococcus aureus strains producing synergohymenotropic toxins.

DNA hybridisation of 309 consecutive Staphylococcus aureus clinical isolates with oligonucleotide probes specific for genes encoding Panton-Valentine leucocidin (luk-PV) and gamma-haemolysin (hlg) revealed that 99% of randomly selected strains carried the hlg locus whereas only 2% harboured the luk-PV as well as the hlg loci. Only 1% of the strains did not possess either gene. In a clinical prospective study of independent S. aureus strains, 58 Panton-Valentine leucocidin (PVL)-producing isolates were shown to be responsible for primary skin infections, mainly furuncles (86%). Phage susceptibility patterns and pulsed field gel electrophoresis (PFGE) profiles of DNA were shown to be polymorphic epidemiological markers of PVL-producing strains. In eight patients with recurrent furuncles, the PVL-producing strains isolated either from furuncles or from the anterior nares were considered to be identical in each based upon phage sensitivity profiles or PFGE patterns.

Porphyria cutanea tarda and hepatitis C viral infection. A clinical and virologic study.

BACKGROUND AND DESIGN: The role of hepatitis C virus (HCV) infection in porphyria cutanea tarda (PCT) is probable since the global HCV antibody prevalence among patients with PCT is about 70%. The purpose of this study was to evaluate the virologic characteristics in 12 patients with sporadic PCT and in one patient with familial PCT. Anti-HCV antibodies were detected by enzyme-linked immunosorbent assay and confirmed by recombinant immunoblot assay. Hepatitis B virus and antihuman immunodeficiency virus markers were also determined. The polymerase chain reaction was performed to detect the following: (1) both positive and negative HCV RNA strands, (2) HCV RNA titer, and (3) HCV RNA genotype. RESULTS: Seven of the 12 patients with sporadic PCT were HCV positive, and the patient with familial PCT was HCV negative. The age at onset of PCT was significantly lower in HCV-positive patients than in HCV-negative patients. The HCV RNA was detected in all patients who had HCV antibodies, and the replicative intermediate of HCV was detected in three of them. The positive RNA titer ranged from 1:10 to 1:10(6). Four patients were infected by HCV genotype I, two by genotype II, and one patient was coinfected by type I and type II. Three of the seven HCV-positive patients also had HBV antibodies, but HBV DNA was never detected. All patients were negative for the human immunodeficiency virus. CONCLUSIONS: The HCV infection rate was high (58%) in this series, and all HCV-infected patients had HCV RNA, reflecting an active replication of the virus. The young age at onset of PCT suggests that HCV is a major triggering factor of PCT. Nevertheless, the clinical changes of PCT were not related to the virologic findings, suggesting an indirect role of HCV.

[Photosensitivity as presenting sign of HIV infection. Control with triple antiretroviral therapy]. / Photosensibilité révélatrice d'une infection par le VIH. Guérison sous trithérapie anti-rétrovirale.

BACKGROUND: We report a case of photosensitivity which occurred as the presenting sign of HIV infection. Photosensitivity regressed completely after introducing antiretroviral tritherapy. CASE REPORT: A 44-year-old woman developed a photo-distributed eczematous eruption which did not respond to topical steroids or hydroxychloroquine. Histologic examination showed eczematous dermatitis. T-cell marker analysis showed a majority of CD8 cells in the infiltrate. The patient was found to be HIV-positive and CD4 counts were markedly reduced to 190/mm3 while CD8 counts were increased to 1260/mm3. Antiretroviral tritherapy cured the photosensitivity. Cure was apparently related to increased CD4 lymphocyte and normalized CD8 lymphocyte counts. DISCUSSION: Photosensitivity was the presenting disorder of HIV infection in this case. Cure of the photosensitivity with antiretroviral tritherapy has not been reported previously. CD8 T-cell infiltration and very low CD4/CD8 ratio would appear to play a key role in the pathogenesis of photosensitivity in these patients.

[Porphyria cutanea tarda and hepatitis C virus infection. Clinical and virological study]. / Porphyrie cutanée tardive et infection par le virus de l'hépatite C. Etude clinique et virologique.

INTRODUCTION: The role of hepatitis C virus (HCV) infection in porphyria cutanea tarda (PCT) is probable since the global antibody prevalence among PCT patients is about 70 p. 100. The purpose of this study was to evaluate the virological characteristics in 12 patients with sporadic PCT and one with familial PCT. METHODS: Anti-HCV antibodies were detected by enzyme-linked immunosorbent assay and confirmed by recombinant immunoblot assay. Hepatitis B virus (HBV) and anti-human immunodeficiency virus (HIV) markers were also determined. The polymerase chain reaction (PCR) was performed in order to detect: 1) both positive and minus HCV strands, 2) HCV RNA titer and 3) HCV RNA genotype. RESULTS: Seven of the 12 patients with sporadic PCT were HCV positive and the patient with familial PCT was HCV negative. The age of onset of PCT was significantly lower in HCV positive patients than in HCV negative patients (p < 0.02). The HCV RNA was detected in all patients who had HCV antibodies, and the replicative intermediate of HCV was detected in 3 of them. The positive RNA titer ranged from 1/10 to 1/10(6). Four patients were infected by HCV genotype I, 2 by genotype II and 1 patient was coinfected by type I and type II. Three of the 7 HCV positive patients also had HBV antibodies, but HBV DNA was never detected. All patients were HIV negative. DISCUSSION: The HCV infection rate was high in this series (58 p. 100), and all HCV infected patients had HCV RNA, reflecting an active replication of the virus. The young age of onset of PCT suggests that HCV is a major triggering factor of PCT. Nevertheless, the clinical changes of PCT were not related to the virological findings, suggesting an indirect role of HCV.

Perianal striated muscle hamartoma associated with hemangioma.

Striated muscle hamartoma is a rare entity which was described only recently. It is a congenital malformation characterized by the presence of striated, mature muscle fibers in the reticular dermis and hypodermis. We describe a striated muscle hamartoma of the perianal region in a female infant associated with an hemangioma in the same area that regressed completely. Including the present patient, only 14 cases of striated muscle hamartomas have been reported, but this association with an hemangioma is unique. The lesion was polypoid and histopathologic examination showed numerous striated muscle fibers located within the dermis.

Panton-Valentine leucocidin and gamma-hemolysin from Staphylococcus aureus ATCC 49775 are encoded by distinct genetic loci and have different biological activities.

Staphylococcus aureus ATCC 49775 produces three proteins recognized by affinity-purified antibodies against the S component of Panton-Valentine leucocidin (LukS-PV) and two proteins recognized by affinity-purified antibodies against the F component of this toxin (LukF-PV). Purification of these proteins and cloning of the corresponding genes provided evidence for the presence of two loci. The first one, encoding Panton-Valentine leucocidin, consisted of two cotranscribed open reading frames, lukS-PV and lukF-PV, coding the class S and the class F components, respectively. The second one coded for a gamma-hemolysin and consisted of two transcription units, the first one encoding an HlgA-like protein, a class S component, and the second one encoding two cotranscribed open reading frames identical to HlgC and HlgB, class S and class F components, respectively, from gamma-hemolysin from the reference strain Smith 5R. It appears that the Panton-Valentine leucocidin from S. aureus ATCC 49775 (V8 strain) should not be confused with leucocidin from ATCC 27733 (another isolate of V8 strain), which had 95% identity with HlgC and HlgB from gamma-hemolysin. The cosecretion of these five proteins led to six possible synergistic combinations between F and S components. Two of these combinations (LukS-PV-LukF-PV and HlgA-LukF-PV) had dermonecrotic activity on rabbit skin, and all six were leukocytolytic on glass-adsorbed leukocytes. Only three were hemolytic on rabbit erythrocytes, the two gamma-hemolysin combinations and the combination LukF-PV-HlgA.

[Atrophic thyroiditis: an unusual course of a Basedow-like variation of Hashimoto disease. Apropos of a case]. / Thyroidite atrophiante: evolution inhabituelle d'une forme basedowienne d'une maladie de Hashimoto.

This case concerns a 27-year-old man with a very high level of anti-thyroid antibody and pretibial elephantiasis myxedema which developed progressively over several years following subtotal thyroidectomy for << hashitoxicosis >>. Complementary resection of the thyroid stump was performed ; under microscopic examination this stump presented an aspect of atrophic thyroiditis. This unusual development towards atrophic thyroiditis raises the problem of the relations between the various forms autoimmune thyroiditis.