Absence of surface expression of feline infectious peritonitis virus (FIPV) antigens on infected cells isolated from cats with FIP

Feline infectious peritonitis virus (FIPV) positive cells are present in pyogranulomas and exudates from cats with FIP. These cells belong mainly to the monocyte/macrophage lineage. How these cells survive in immune cats is not known. In this study, FIPV positive cells were isolated from pyogranulomas and exudates of 12 naturally FIPV-infected cats and the presence of two immunologic targets, viral antigens and MHC I, on their surface was determined. The majority of the infected cells were confirmed to be cells from the monocyte/macrophage lineage. No surface expression of viral antigens was detected on FIPV positive cells. MHC I molecules were present on all the FIPV positive cells. After cultivation of the isolated infected cells, 52 ± 10% of the infected cells re-expressed viral antigens on the plasma membrane.

In conclusion, it can be stated that in FIP cats, FIPV replicates in cells of the monocyte/macrophage lineage without carrying viral antigens in their plasma membrane, which could allow them to escape from antibody-dependent cell lysis.

Investigation of a broad-spectrum PCR assay for human papillomaviruses in screening benign lesions of the upper aerodigestive tract

BACKGROUND

A variety of different human papillomavirus (HPV) types can be found in benign and malignant lesions of the upper aerodigestive tract. Therefore a broad-spectrum assay is needed for screening reasons.

METHODS

A PCR system with degenerate consensus primers originating from a very conserved region (e.g. L1) of the HPV genome was applied. The sensitivity level was improved by combining PCR and nested PCR.

RESULTS

A total of 27 biopsies from laryngeal papillomas (9), exophytic (3) and inverted (6) papillomas of the nasal cavity or paranasal sinuses, papillomas of the uvula or soft palate (5), leukoplakias of the larynx (2), seborrheic keratosis (1) and granulation tumor of the tongue (1) were analyzed by the broad-spectrum PCR system. Sixteen cases showed a positive result in either PCR or nested PCR or both.

CONCLUSIONS

It was shown that the applied broad-spectrum PCR system is a reliable tool in the detection of HPV DNA in benign lesions of the upper aerodigestive tract.

Bronchocentric granulomatosis associated with influenza-A virus infection

Bronchocentric granulomatosis is an unusual pathologic entity that is characterized by a necrotizing granulomatous inflammation surrounding the airways. The diagnosis is usually made retrospectively, after histopathologic examination of an open-lung biopsy or resection of a pulmonary lesion. Although the aetiology has not been fully elucidated, the current pathogenetic mechanism is considered to be an immunologic reaction against endobronchial antigens, since most patients exhibit signs of bronchial asthma, eosinophilia and allergic bronchopulmonary aspergillosis. However, non-asthmatic patients may develop bronchocentric granulomatosis without signs for endobronchial fungal infections, but probably as a consequence of other pulmonary infections. An 80-year-old female patient presented with high fever and bilateral pulmonary infiltrates and nodules. After extensive investigations and open-lung biopsy, the diagnosis bronchocentric granulomatosis was established that was possibly associated with an influenza-A virus infection. Treatment consisted of immunosuppressive drugs (prednisone and cyclophosphamide), which led to complete clinical and radiological recovery.

Hepatic granuloma in chronic hepatitis C

We report the findings in a 54-year-old male with chronic hepatitis C with granulomas liver biopsy. Unfortunately, this patient died before treatment could be started.

Florid Granulomatous Reaction in Epstein-Barr Virus-positive Nonendemic Burkitt Lymphomas

Epithelioid cell granulomas have been reported in association with a wide range of neoplasms including malignant lymphomas. In lymphoma, this refers mainly to Hodgkin disease and T-cell-derived non-Hodgkin lymphomas where a granulomatous reaction is probably evoked by aberrant cytokine production in the tumor cells or other cells composing the tumor background. Here we report on four cases of sporadic Burkitt lymphoma with unusual florid granulomatous reaction. In all samples, the tumor cells were admixed with numerous epithelioid cells that formed clusters and granulomatous lesions. No microorganisms could be detected at the tissue level, and there were no clinical or laboratory indications of an underlying immunodeficiency. The lymphomas harbored a specific morphology and immunophenotype of Burkitt lymphoma, and the presence of translocation breakpoint in MYC gene was confirmed by interphase fluorescence in situ hybridization. In all four patients, the lymphoma was associated with Epstein-Barr virus infection, detected by EBER in situ hybridization and the latency I phenotype as defined by lack of expression of LMP1. All four patients were treated with polychemotherapy, achieved a complete remission, and are alive without evidence of disease. We draw attention to this unusual phenomenon as it caused difficulties in interpretation and delayed diagnosis and hypothesize on the possible role of Epstein-Barr virus products.

Hepatic granulomas: a 10 year single centre experience

BACKGROUND

Epithelioid granulomas have been reported in 2-15% of unselected liver biopsies, with numerous underlying aetiologies described. However, all UK series were reported before identification of hepatitis C virus (HCV).

AIM

To evaluate the current aetiologies of hepatic granulomas and to assess the prognosis for the "idiopathic" group, in which all investigations for a recognised cause were negative or normal.

METHODS

A retrospective review of patient case notes between 1991 and 2001; all patients who had a liver biopsy at Glasgow Royal Infirmary revealing epithelioid granulomas had their case notes and liver biopsies reviewed and a standard proforma completed.

RESULTS

Over the study period, 1662 liver biopsies were performed. Hepatic granulomas were found in 63. Of those identified, 47 were female, with a mean age of 42 years (range, 17-81). Underlying aetiologies were as follows: primary biliary cirrhosis (PBC; 23.8%), sarcoidosis (11.1%), idiopathic (11.1%), drug induced (9.5%), HCV (9.5%), PBC/autoimmune hepatitis (AIH) overlap (6.3%), Hodgkin lymphoma (6.3%), AIH (4.8%), tuberculosis (4.8%), resolving biliary obstruction (3.2%), and other single miscellaneous causes (9.5%). Of the seven patients with idiopathic hepatic granulomas, one was lost to follow up, one died of stroke, and the remaining five were well with no liver related morbidity at a mean follow up of 6.2 years.

CONCLUSIONS

The aetiology of hepatic granulomas is broad ranging, with HCV an important cause in this population. Despite extensive investigations, a 10-15% of patients still had "idiopathic" hepatic granulomas. However, the prognosis for this last group appears to be excellent.

Expression of monocyte chemoattractant protein-1 but not interleukin-8 in granulomatous lesions in lymph nodes from pigs with naturally occurring postweaning multisystemic wasting syndrome

Monocyte chemoattractant protein-1 (MCP-1) but not interleukin-8 (IL-8) was detected by in situ hybridization using a nonradioactive digoxigenin-labeled complementary DNA probe in granulomatous lesions of lymph nodes from 20 pigs with naturally occurring postweaning multisystemic wasting syndrome (PMWS). Complementary DNA probes of 375 and 266 base pairs for MCP-1 and IL-8, respectively, were generated by reverse transcription-polymerase chain reaction. The 20 pigs with PMWS had distinct positive hybridization signals for MCP-1 but not for IL-8. The hybridization signals for MCP-1 were strictly confined to the cells with granulomatous lesions, including macrophages and multinucleated giant cells. A very close cell-to-cell correlation between MCP-1 and porcine circovirus 2 was seen in serial sections of lymph nodes. Results of this study indicate that MCP-1 expression may play a role in the pathogenesis of granulomatous inflammation in pigs with PMWS.

A comparison of lymphatic tissues from cats with spontaneous feline infectious peritonitis (FIP), cats with FIP virus infection but no FIP, and cats with no infection

Lymphatic tissues (spleen, mesenteric lymph nodes, thymus) from 24 cats with spontaneous feline infectious peritonitis (FIP) were examined by light microscopy and immunohistochemistry for cellularity, cellular composition, and degree of cellular turnover. Additionally, the formation of granulomatous lesions in lymphatic tissues in cats with FIP was examined. For comparison, tissues from 14 specific pathogen-free (SPF) cats and seven cats infected with FIP virus (FIPV; as the result of long-term exposure) but free from FIP were examined. In cats with FIP, the precardial mediastinum (including site of the thymus) and mesenteric lymph node parenchyma were often affected by granulomatous-necrotizing processes. In general, lymphoid tissues showed T- and B-cell depletion, often including massive to complete thymic involution or atrophy. In some cases, the number of apoptotic lymphocytes was increased in lymphoid follicles as well as in T-cell zones. The number of macrophages was increased in the splenic red pulp. In contrast, the FIPV-exposed cats without FIP generally showed a distinct lymphoid hyperplasia. The findings indicated that the major difference in lymphatic tissues between FIPV-infected cats with FIP and those without FIP was the development of lymphocyte depletion in the first group and lymphocyte proliferation in the second.

Inhibitory and enhancing effects of IFN-gamma and IL-4 on SHIV(KU) replication in rhesus macaque macrophages: correlation between Th2 cytokines and productive infection in tissue macrophages during late-stage infection

HIV-1 is dual-tropic for CD4+ T lymphocytes and macrophages, but virus production in the macrophages becomes manifest only during late-stage infection, after CD4+ T cell functions are lost, and when opportunistic pathogens begin to flourish. In this study, the SHIV/macaque model of HIV pathogenesis was used to assess the role of cytokines in regulating virus replication in the two cell types. We injected complete Freund's adjuvant (CFA) intradermally into SHIV(KU)-infected macaques, and infused Schistosoma mansoni eggs into the liver and lungs of others. Tissues examined from these animals demonstrated that macrophages induced by CFA did not support viral replication while those induced by S. mansoni eggs had evidence of productive infection. RT-PCR analysis showed that both Th1 (IL-2 and IFN-gamma) and Th2 cytokines (IL-4 and IL-10) were present in the CFA lesions but only the Th2 cytokines were found in the S. mansoni lesions. Follow-up studies in macaque cell cultures showed that whereas IFN-gamma caused enhancement of virus replication in CD4+ T cells, it curtailed viral replication in infected macrophages. In contrast, IL-4 enhanced viral replication in infected macrophages. These studies strongly suggest that cytokines regulate the sequential phases of HIV replication in CD4 T cells and macrophages.

HTLV-I-associated granulomatous T-cell lymphoma in a child

Adult T-cell leukemia/lymphoma (ATLL) is a T-cell malignancy closely associated with human T-cell lymphotropic virus-1 (HTLV-I). Because of its long latency period, ATLL occurs almost exclusively in adults. We report a case of a 13-year-old boy with an 8-year history of skin eruptions. After complete evaluation, a diagnosis of HTLV-I-associated lymphoma/leukemia was made. The T-cell lymphoma exhibited a granulomatous histomorphology. There have been very few reports of ATLL presenting in childhood and none, to our knowledge, demonstrating granulomatous histology. We conclude that ATLL may rarely present as a chronic granulomatous eruption in a child.

Virulence-associated protein characterisation of Rhodococcus equi isolated from bovine lymph nodes

Rhodococcus equi has a low pathogenicity in cattle, but it occasionally causes lymph node granulomas, which are detected at abattoir post mortem inspection, and must be distinguished from tuberculous granulomas. Lymph node lesions were detected in 6719 cattle, from a total of 3,263,622 cattle examined post mortem in abattoirs, in the Republic of Ireland, during 1997 and 1998. Histological examination was performed on all lesions, principally for the purpose of identifying animals with tuberculosis. A total of 1122 of the lesions were cultured on blood agar and on Stonebrinks and Lowenstein-Jensen medium containing pyruvate, because the histological findings were difficult to interpret or were suggestive of R. equi infection. R. equi was isolated from 264 lesions. Almost all of the R. equi granulomas were confined to a single lymph node, and were present predominantly in the retropharyngeal, bronchial and mediastinal lymph nodes. R. equi granulomas were present in a significantly higher proportion of the lesions detected in steers and heifers compared to cows. The prevalence in the total population of 3.3 million cattle examined post mortem was 0.008%. The 15-17kDa antigens, associated with virulence in this organism, and the 20kDa antigen, associated with intermediate virulence, were not detected in isolates from 146 cattle, analysed by immunoblot assays. A PCR assay to detect the plasmid gene encoding the 15-17kDa antigens was also negative for isolates from these 146 animals. Plasmids were not detected in 30 isolates which were examined.

Diseases of the eye of farmed shrimp Penaeus monodon

Lesions were found in the eyes of cultured shrimp Penaeus monodon that displayed non-specific signs of disease, including lethargy, dark pigmentation, brown gills, empty midgut, anorexia, white tail muscle, necrosis of uropods and fouled cuticle. Eye lesions were associated with sexual development in moribund shrimp in at least 1 disease event. Suppurative inflammation, granuloma and malacia were observed in histological examination of the eye and the causative agents of lesions appear to be Vibrio spp. and a rod-shaped virus (similar to Lymphoid Organ Virus, Gill-Associated Virus [GAV] and Yellow-Head Virus). Suppurative inflammation was characterised by edema, infiltration of haemocytes and local sites of abscesses. Eyes with granuloma usually appeared white in pond-side examinations, and histology showed that fibrous tissue replaced ommatidia, ganglia and internal structures of the eye. Malacia of the eye was characterised by necrosis of nervous tissue, vacuolation and vascular proliferation in the medulla ganglia. Levels of presumptive Vibrionaceace were high in moribund specimens and Gram-negative rods were observed in some specimens as free particles in the interstitial fluid and haemolymph in the eye. Transmission electron microscopy showed that nerve cells in the fasciculated zone (near the basement membrane) contained cytoplasmic vesicles (1 to 3 microm in diameter) with particles (15 to 26 nm in diameter) and rod-shaped nucleocapsids. The rods were similar to those of GAV and were 130 to 260 nm long, 10 to 16 nm in diameter and had helical symmetry with a screw-like thread (2.4 to 3.5 nm pitch). Also, unidentified enveloped virions, averaging 74 nm in diameter, were observed in cytoplasmic vesicles in the fasciculated zone. In conclusion, it is suggested that bacterial and viral infections of the eye could result in impaired neuroendocrine functions, which may cause a range of clinical signs of disease.

Lymphohistiocytic and granulomatous phlebitis in penile lichen sclerosus

Lichen sclerosus (LS) is a chronic inflammatory disease of unknown etiology that may affect the genital and/or extragenital skin of individuals of either sex at all ages. In boys, the prepuce is the most common site of involvement. The diagnostic criteria of LS include the presence of inflammatory infiltrates mainly composed of T lymphocytes. We report on two cases of LS of the prepuce because of the unusual feature of lymphocytic (CD45RO+ and CD20+), histiocytic (CD68+), and granulomatous phlebitis. This lesion was not present in a group of another 18 cases of childhood penile LS. We have not been able to find any references describing and illustrating inflammatory involvement of the dermal vein walls in LS. Unlike the data reported in the literature, the dermal inflammatory infiltrates of these two cases showed a similar proportion of B and T lymphocytes in addition to frequent CD68+ histiocytes.

[Lung and bone marrow granulomas associated with human parvovirus B19 infection]

A 56-year-old man was admitted with flu-like symptoms, and his platelet count abruptly decreased. A chest X-ray film showed granular shadows, and lung and bone marrow specimens disclosed non-caseating epithelioid cell granulomas. The patient's serum IgM titer for human parvovirus (HPV) B19 was elevated. Our conclusion was that HPV B19 must be kept in mind as a possible pathogenic agent of granuloma formation.

Systemic granulomatous arteritis associated with Epstein-Barr virus infection

A 61-year-old woman initially presented with symptoms and findings reminiscent of infectious mononucleosis, and her illness then took a rapidly fatal course. Autopsy revealed widespread granulomatous arteritis, with multinucleated giant cells but without eosinophils and fibrinoid necrosis, affecting small arteries and arterioles and infiltration of haemophagocytic histiocytes into many organs. In situ hybridization with Epstein-Barr virus (EBV)-specific oligonucleotide probes showed positive signals in the infiltrating immune cells and epithelial and endothelial cells of the affected organs. EBV-associated haemophagocytic syndrome (EBV-AHS) with systemic granulomatous arteritis was diagnosed. From the immunophenotypes of the infiltrating immune cells, a possible role of CD4+ T-cells in the pathogenesis of this haemophagocytic syndrome and granulomatous vasculitis was suggested.

Posttransplant liver granulomatosis associated with hepatitis C?

BACKGROUND

Liver granulomatosis is an occasional finding in posttransplant liver biopsies. Its diagnosis is made more difficult by the variety of conditions that can lead to it. In the nontransplant setting, the association of liver granulomatosis and hepatitis C virus (HCV) infection has occasionally been described.

METHODS

We describe the case of a patient with a liver transplantation for an HCV-associated cirrhosis who developed an alteration of liver tests. Granulomatosis was detected on the liver biopsy.

RESULTS

Other causes of granulomatosis were satisfactorily excluded. The development of the lesions coincided with a viral flare-up.

CONCLUSION

We think that HCV can be listed among the possible causes of liver granulomas in the posttransplant setting and that it must be considered in the differential diagnosis of this condition.

Cutaneous reactions at sites of herpes zoster scars: an expanded spectrum

Several types of cutaneous lesions have previously been described at the sites of herpes zoster scars. We describe 16 patients with cutaneous lesions which had developed on herpes zoster scars. Biopsies were taken from these lesions, and a polymerase chain reaction assay was used to detect the viral genome in paraffin-embedded specimens. Histopathological findings enabled diagnosis of nonspecific granulomatous dermatitis in five patients, granulomatous vasculitis in two patients, lichen sclerosus in two patients, and pseudolymphoma, keloid, sarcoidal granuloma, granuloma annulare, granulomatous folliculitis, lichen planus and cutaneous Rosai-Dorfman disease, each in one patient. Varicella-zoster virus DNA was not identified in any of the patients. Granulomatous folliculitis, lichen sclerosus and cutaneous Rosai-Dorfman disease have not previously been described in herpes zoster scars, but they are three new cutaneous reaction patterns that may have developed within these scars. Our investigations indicate that the cutaneous reactions appearing in herpes zoster scars are not due to the persistence of varicella-zoster virus DNA within the lesions.

Herpes zoster sine herpete. A potential cause of iridoplegic granulomatous iridocyclitis

OBJECTIVE

Herpes zoster ophthalmicus (HZO) is a recurrence of varicella zoster virus involving cranial nerve V-1, but does not always have skin manifestations. The objective of this work is to study iridoplegic granulomatous iridocyclitis as an acute, fulminant iridocyclitis that probably is caused by the recurrence of varicella zoster virus without skin eruptions.

PARTICIPANTS

The author reports 15 cases of iridoplegia granulomatous iridocyclitis with involvement of the anterior uveal tract without known skin eruptions.

RESULTS

All patients have had a clinical course of iridocyclitis closely resembling those cases of herpes zoster with skin eruptions. Nine of the 15 are documented to have had a recurrence of varicella zoster virus with an appropriate rise and fall of systemic titers. The remaining six patients had clinical findings, including loss of accommodation, iridoplegia, and sectoral iris atrophy that were more typical for HZO than other infectious agents.

CONCLUSIONS

Iridoplegic granulomatous iridocyclitis is a newly described, acute, fulminant uveitis probably caused by a herpes virus and most probably by varicella zoster virus. Herpes zoster sine herpete (erupticum) should be suspected as a potential diagnosis in patients with appropriate anterior segment manifestations. Further study is necessary to discern if any of such cases could be caused by herpes simplex.

Rationale for the use of contrast media in MR imaging

Understanding the rationale of contrast media use in MR imaging is based on knowledge of the blood brain barrier (BBB) and the pathophysiology of infectious agents attacking the central nervous system. This article focuses on the relationship between BBB structures and functions in healthy and unhealthy conditions and contrast media in patients with acquired immunodeficiency syndrome.

Detection and comparative analysis of persistent measles virus infection in Crohn's disease by immunogold electron microscopy

AIMS

To determine the specificity of persistent measles virus infection in intestinal samples from Crohn's disease patients using quantitative immunogold electron microscopy. To compare the results with samples from ulcerative colitis, a granulomatous inflammatory control (tuberculous lymphadenitis), and a positive control.

METHODS

Formalin fixed, paraffin embedded intestinal tissue from patients with Crohn's disease was reprocessed and stained with antimeasles nucleocaspid protein primary antibody followed by 10 nm gold conjugated secondary antibody. Tissue samples were taken from granulomatous and non-granulomatous areas of the intestine. Intestinal samples from patients with ulcerative colitis, tuberculous lymphadenitis, or acute mesenteric ischaemia were similarly processed. Brain tissue from a patient with subacute sclerosing panencephalitis (SSPE) was used as the positive control. Duplicate sections of all tissues were processed without the primary antibody. Stained specimens were examined by electron microscopy.

RESULTS

In Crohn's disease patients, 8/9 foci of granulomatous inflammation and 0/4 foci of non-specific inflammation were positive for measles virus. Of controls, 0/5 non-inflamed intestinal tissues, 1/8 tuberculous tissues, 1/5 ulcerative colitis tissues, and 1/1 SSPE tissues were positive. Gold grain counts per nuclear field-of-view in both Crohn's disease granulomas (43.29) and SSPE (36.94) were significantly higher than in tissues from patients with ulcerative colitis (13.52) or tuberculous lymphadenitis (15.875), and nongranulomatous areas of Crohn's disease (4.89) (p < 0.001, p < 0.001, p = 0.0006, respectively), with no significant difference between Crohn's disease and SSPE (p > 0.1). In both SSPE and Crohn's disease staining was confined to a small population of cells exhibiting characteristic cytopathology.

CONCLUSION

These data support a role for measles virus in the aetiology of Crohn's disease.

Granulomas and hepatitis C

Hepatitis C (HCV) is associated with a number of characteristic histological features. A recent paper has identified an increased frequency of granulomas in resection specimens from cases of HCV. We have carried out a retrospective study of 155 cases of HCV to assess the frequency of granulomas in biopsy specimens. We had two control groups: 151 cases of hepatitis B (HBV) and 129 cases of alcohol induced liver disease. Granulomas were found in 14 cases of HCV (10%), three cases of HBV (2%) and three cases of alcohol induced liver disease (2%). Granulomas were significantly commoner in cases of HCV than in the other two groups. Of the 14 cases of HCV, the granulomas could be ascribed to another cause in seven cases. When the analysis was carried out, excluding those granulomas which could be ascribed to another cause, they were still significantly commoner in cases of HCV. We conclude that granulomas are more frequent in HCV but that in half of cases in which they are found another cause can be identified. This means that if granulomas are seen in association with hepatitis C another aetiology should be sought before ascribing them to HCV.