Critical role of STIR MRI in early detection of post-streptococcal periostitis with dysproteinaemia (Goldbloom's syndrome).

OBJECTIVES: In 1966, Goldbloom et al. described two children who developed a peculiar clinical picture characterized by intermittent daily bone pain in the lower limbs, fever spikes, increased acute phase reactants and dysproteinaemia. The syndrome occurred two weeks after a group A ß-haemolytic streptococcus infection. So far, only a few cases have been reported in the medical literature in English. METHODS: We report two further cases of Goldbloom's syndrome with a review of the literature in English. RESULTS: Our two patients lived in the same Italian region and presented their syndrome onset a week apart. Early use of STIR MRI revealed an atypical metaphyseal hyperintensity in the femurs and tibias. X-ray showed periosteal hyperostosis. A short cycle of corticosteroids led to rapid recovery of symptoms and disappearance of bone changes. CONCLUSIONS: The reported cases highlight a likely under-recognised post-streptococcal inflammatory periosteal reaction and emphasise the diagnostic utility of the newer imaging modalities.

Expansion of Tfh-like cells during chronic Salmonella exposure mediates the generation of autoimmune hypergammaglobulinemia in MyD88-deficient mice.

The role of TLR signaling in linking the innate and adaptive immune systems has been a controversial issue that remains to be solved. Here, we determined whether MyD88-dependent TLR signals are required for the generation of B-cell responses during chronic Salmonella infection. Oral administration of recombinant attenuated Salmonella enterica serovar Typhimurium vaccine (RASV) strain in MyD88(-/-) mice resulted in chronic infection. Infection was accompanied by enlarged germinal centers and hypergammaglobulinemia with anti-double-stranded DNA (dsDNA)-specific Ab in sera, and the deposition of immune complexes in the kidneys, suggesting onset of autoimmunity. CD4(+) T cells expressing PD-1, CXCR5, ICOS, and IL-21 were dramatically increased in chronically infected mice, indicating the expansion of follicular helper T (Tfh)-like cells. Of note, the depletion of CD4(+) T cells completely blocked the generation of polyclonal IgG Ab in sera after oral RASV challenge. Inflammatory myeloid cells expressing CD11b and Gr-1 accumulated in high numbers in the spleen of MyD88(-/-) mice. Interestingly, the blockade of PD-1 or ICOS significantly reduced the hypergammaglobulinemia and dsDNA-specific autoantibody production. Overall, these results suggest that Tfh-like cells in chronic bacterial infection trigger autoimmune hypergammaglobulinemia in a PD-1- and ICOS-dependent manner.

Candida endocarditis in a child with hyperimmunoglobulinemia E syndrome.

Hyperimmunoglobulin E syndrome (HIE) is a disorder characterized by extremely elevated serum levels of IgE and recurrent infections. Patients are particularly predisposed to have staphylococcal abscesses, usually involving skin, lungs, and joints; but they are also at risk for infections with other bacteria and fungi. We report the case of a 46-month-old boy with HIE who had Candida endocarditis and sepsis with a large fungal mass extending through the tricuspid valve and into the surrounding heart tissue, requiring surgical excision and replacement with a prosthetic valve. He had an indwelling central line for previous antibiotic therapy and had oral thrush for a month before presentation, which had been treated with oral nystatin. He was first seen with very dark urine, a new murmur, petechial rash, in shock, and disseminated intravascular coagulation. The white blood cell count was 38,700 with 70% segmented neutrophils, 9% banded neutrophils, 15% lymphocytes, 4% monocytes, and 2% eosinophils. Hemoglobin was 7.1, and platelet count was 14,000. Prothrombin time was 15.5, and partial thromboplastin time was 31; fibrinogen level was 110 mg/ml, and fibrin degradation products were greater than 40 mg/ml. Serum IgE was 38,664 and 44,510 on repeat measurement. He has had recurrent staphylococcal pneumonias with pneumatoceles, twice requiring segmental lung resection. Blood and tricuspid valve cultures grew Candida albicans. He was treated with amphotericin and flucytosine, and later switched to fluconazole, with good response to therapy. A literature search revealed no other reported case of Candida endocarditis in patients with HIE. Fungai endocarditis is a rare complication, which may occur in patients with HIE and indwelling central catheters.

The role of somatic structure of the fungus Paracoccidioides brasiliensis upon B cell activation in experimental paracoccidioidomycosis.

In this study, we report an increase of the number of antibody-secreting cells and the augmentation of antibody production against unrelated antigens in mice infected with the fungus P. brasiliensis, as well as in mice inoculated with cell wall preparation isolated from P. brasiliensis (CW). The immunomodulatory effect of the live fungus and the CW preparation was dose-dependent, and their actions were mainly restricted to the i.v. or i.p. inoculation simultaneously with the sheep erythrocyte challenge by the i.v. route or restricted to i.p. inoculation of CW when bovine serum albumin (BSA) antigen was used. The dependence of antibody production on different routes of CW inoculation was correlated with the number of antigen-specific B cells in the spleen as determined by direct and reverse plaque-forming cell assays. The immunization schedules using CW preparation caused a preferential production of IgM and IgG3 antibodies. The results also showed that the hyperactive humoral immune response of mice induced by i.p. inoculation of CW was devoid of polyclonal B cell activation compared with the effects observed for the lipopolysaccharide (LPS)-treated groups. Paracoccidioides brasiliensis CW components may have potent immunological properties related to the non-specific B cell activation found in paracoccidioidomycosis.

Long-term dietary vitamin E retards development of retrovirus-induced disregulation in cytokine production.

A 15-fold increase in dietary vitamin E (160 IU/liter) normalized hepatic and serum levels of vitamin E normally reduced by retrovirus infection. It also significantly retarded development of splenomegaly and hypergammaglobulinemia induced by retrovirus infection, while significantly restoring release of interleukin-2 (IL) and interferon-gamma by splenocytes which are suppressed by retrovirus infection. Retrovirus infection elevated production of IL-4 and IL-6 by splenocytes, but this elevation was inhibited by vitamin E. Increased levels of IL-6 and tumor necrosis factor-alpha produced by splenocytes during progression to murine AIDS were also inhibited by vitamin E. Vitamin E supplementation also helped restore retrovirus-suppressed splenocyte proliferation. These data indicate that vitamin E supplementation can help overcome retrovirus-induced reduction in tissue vitamin E, modulate cytokine release, and normalize immune dysfunctions during progression to murine AIDS.

Infections with Babesia canis and Ehrlichia canis in dogs in Zimbabwe.

Of 105 dogs examined at a veterinary hospital in Harare, Zimbabwe, 52 per cent had antibodies reactive with Ehrlichia canis in indirect fluorescent antibody tests, 26 per cent had Babesia canis parasites in peripheral blood smears and 17 per cent had both infections. None of the dogs with serological evidence of ehrlichiosis had typical E canis morulae detectable in blood smears. The infections were regarded as incidental findings not readily related to the reasons for examination in 46 per cent of the dogs with antibodies to E canis and 17 per cent of the dogs with both infections. The most common laboratory abnormalities were anaemia and thrombocytopenia and the prevalence and severity of these in concurrent infections were intermediate to those found in individual infections. There were no pathognomonic clinical signs or laboratory abnormalities which could be used to distinguish between individual and concurrent infections. However, there was a significantly higher prevalence of non-regenerative anaemia in dogs with antibodies to E canis than in dogs with both infections. The prevalence of thrombocytopenia was significantly higher in dogs with babesiosis than in dogs with antibodies to E canis and the prevalence of hyperglobulinaemia was significantly higher in dogs with both infections than in dogs with antibodies to E canis.

Cell wall fractions from Paracoccidioides brasiliensis induce hypergammaglobulinemia.

The antibody response against the antigen sheep red blood cells (SRBC) was investigated in mice pre-treated with formalin-killed Paracoccidioides brasiliensis or with cell wall fractions of the fungus. Pre-treatment with P. brasiliensis, as well as with the Fl fraction and beta-glucan significantly increased the anti-SRBC antibody response in the experimental groups as compared to the control group that received only SRBC. This immunomodulatory effect varied with the different doses employed and with pre-treatment time. We conclude that the cell wall fractions of P. brasiliensis might play an important role in the hypergammaglobulinemia associated with Paracoccidioidomycosis.

False positive reaction of heat-inactivated sera in enzyme-linked immunosorbent assay for antibody to hepatitis C virus.

Specimens were heated at 56 degrees C or 62 degrees C to analyze the mechanisms of false positive reactions in the Ortho enzyme-linked immunosorbent assay (ELISA) for the detection of antibody to hepatitis C virus (HCV). The highest correlation was obtained between the difference in HCV antibody titer of 56 degrees C-heated and native sera and IgG concentration. Monoclonal IgG gammopathy sera developed marked increases in the titer by preheating. However, slight increases after preheating were observed in monoclonal IgA gammopathy sera. Similar increases in the titer by preheating were also demonstrated in immunoglobulin products containing IgG. Direct bindings of denatured IgG with C100-3 and 5-1-1 antigens were shown in recombinant immunoblot assay (RIBA). These results could show the participation of denatured IgG in the false positive reaction in Ortho-HCV-ELISA. Caution is necessary in evaluating the anti-HCV antibody titers of heat-inactivated sera.

Immune complexes that bind to ELISA plates not coated with antigen in mice infected with lactate dehydrogenase-elevating virus: relationship to IgG2a- and IgG2b-specific polyclonal activation of B cells.

We have further investigated the nature of IgG-containing complexes of 150-300 kD that rapidly appear in the circulation of mice of various strains after infection with lactate dehydrogenase-elevating virus (LDV) and are recognized and quantitated by their binding in the presence of 0.05% Tween 20 to certain enzyme-linked immunosorbent assay (ELISA) plates with high protein affinity that have not been coated with protein antigen (5). These binding complexes have been found to contain primarily IgG2a or, in some mice, IgG2b. Their isotype specificity and time course of formation correlated with those of the polyclonal production of immunoglobulins in these mice, as measured by increases in total IgG2a or IgG2b in the circulation. In contrast, anti-LDV antibodies exhibited much broader isotype specificities in all mouse strains investigated. Depletion of BALB/c mice of CD4+T cells or lack of T cells in nude Swiss mice only partly reduced the polyclonal activation of B cells and the formation of ELISA plate-binding complexes, whereas anti-LDV antibody formation was completely blocked. Only a small proportion of the total IgG2a or IgG2b formed as a result of the LDV-induced polyclonal activation of B cells was recovered in plate-binding complexes, which sedimented in sucrose density gradients between 150 and 300 kD. Diverse monoclonal antibodies of different IgG isotopes did not bind to the plates at concentrations at which LDV-induced immune complexes exhibited binding activity. We suggest that the LDV-induced immune complexes do not contain anti-LDV antibodies, but are complexes of auto-antibodies and self-antigen(s). However, additional features must be responsible for the high affinity of these complexes for ELISA plates since various immune complexes formed in vitro failed to bind to the plates, and binding activity of the immune complexes formed in LDV-infected mice could not be regenerated in vitro once the complexes had been dissociated by a low pH treatment.

A case of diffuse panbronchiolitis (DPB) with benign monoclonal IgA gammopathy and IgA nephropathy with monoclonal IgA deposition.

A case of diffuse panbronchiolitis (DPB), associated with benign monoclonal IgA gammopathy and IgA nephropathy is described. The IgA deposition in the glomeruli of the patient was identified as consisting mainly of the monoclonal IgA having the same idiotype as that of serum monoclonal IgA. Recurrent infections of Hemophilus influenzae and Pseudomonas aeruginosa in the respiratory tract might have enhanced IgA-mediated immunity at the mucosal surface of the bronchiole, and ultimately induced monoclonal IgA gammopathy and IgA nephropathy.