A Patient with Necrotizing Vasculitis Related to Sarcoidosis, which Was Diagnosed via Immunohistochemical Methods Using Propionibacterium acnes-specific Monoclonal Antibodies

Propionibacterium acnes (P. acnes) is a commensal bacterium indigenous to the skin. Previous reports have suggested that infection with P. acnes causes sarcoidosis, a systemic granulomatous disease. We present the case of a 63-year-old woman who developed subcutaneous nodules. A skin biopsy revealed necrotizing vasculitis and noncaseating granulomas, which are characteristic of sarcoidosis. Immunohistostaining revealed a P. acnes skin infection, which led to the diagnosis of sarcoidosis. Minocycline treatment resolved the infection and improved the patient's symptoms. We herein report a case in which immunohistochemistry was useful in the diagnosis of sarcoidosis.

Crohn’s disease and extra intestinal granulomatous lesions

Crohn’s disease (CD) is an inflammatory bowel disease with a multifactorial etiology. Clinical features include mucosal erosion, diarrhea, weight loss and other complications such as formation of granuloma. In CD, granuloma is a non-neoplastic epithelioid lesion, formed by a compact aggregate of histiocytes with the absence of a central necrosis, however, the correlation among CD and the formation of granulomas is unknown. Many cases of granulomas in the extracellular site, related to CD, have been reported in the literature. These granulomas, at times, represented the only visible manifestation of the pathology. Extra intestinal granulomas have been found on ovaries, lungs, male genitalia, female genitalia, orofacial regions and skin. From the data in the literature it could be hypothesized that there is a cross-reaction of the immune system with similar antigenic epitopes belonging to different sites. This hypothesis, if checked, can place CD not only among inflammatory bowel disease but also among inflammatory diseases with systemic involvement.

Clinical tool for disease phenotyping in granulomatous lung disease

Background

Exposure to beryllium may lead to granuloma formation and fibrosis in those who develop chronic beryllium disease (CBD). Although disease presentation varies from mild to severe, little is known about CBD phenotypes. This study characterized CBD disease phenotypes using longitudinal measures of lung function.

Methods

Using a case-only study of 207 CBD subjects, subject-specific trajectories over time were estimated from longitudinal pulmonary function and exercise-tolerance tests. To estimate linear combinations of the 30-year values that define underlying patterns of lung function, we conducted factor analysis. Cluster analysis was then performed on all the predicted lung function values at 30 years. These estimates were used to identify underlying features and subgroups of CBD.

Results

Two factors, or composite measures, explained nearly 70% of the co-variation among the tests; one factor represented pulmonary function in addition to oxygen consumption and workload during exercise, while the second factor represented exercise tests related to gas exchange. Factors were associated with granulomas on biopsy, exposure, steroid use and lung inflammation. Three clusters of patients (n = 53, n = 59 and, n = 95) were identified based on the collection of test values. Lower levels of each of the factor composite scores and cluster membership were associated with baseline characteristics of patients.

Conclusions

Using factor analysis and cluster analysis, we identified disease phenotypes that were associated with baseline patient characteristics, suggesting that CBD is a heterogeneous disease with varying severity. These clinical tools may be used in future basic and clinical studies to help define the mechanisms and risk factors for disease severity.

Hepatic and Gastric Involvement in a Case of Systemic Sarcoidosis Presenting with Rupture of Esophageal Varices

A 46-year-old woman presented with massive hematemesis, caused by the rupture of esophageal varices. The laboratory investigations showed pancytopenia, and imaging tests revealed hepatosplenomegaly and ascites. A diagnosis of systemic sarcoidosis was made based on biopsies of the liver, stomach, lungs, heart, and skin. Although fat deposition was predominant, non-caseating granuloma and cirrhotic changes were found in the liver. Non-caseating granuloma was also identified in a biopsy specimen from minute depressions of the gastric folds. This case illustrates the rare involvement of the digestive system in a case of systemic sarcoidosis.

IN VIVO ANTI-INFLAMMATORY EFFECTS OF TARAXASTEROL AGAINST ANIMAL MODELS

BACKGROUND

Traditional Chinese medicine Taraxacum officinale has been widely used to treat various inflammatory diseases. Taraxasterol is one of the main active components isolated from Taraxacum officinale. Recently, we have demonstrated that taraxasterol has the in vitro anti-inflammatory effects. This study aims to determine the in vivo anti-inflammatory effects of taraxasterol against animal models.

MATERIALS AND METHODS

Anti-inflammatory effects were assessed in four animal models by using dimethylbenzene-induced mouse ear edema, carrageenan-induced rat paw edema, acetic acid-induced mouse vascular permeability and cotton pellet-induced rat granuloma tests.

RESULTS

Our results demonstrated that taraxasterol dose-dependently attenuated dimethylbenzene-induced mouse ear edema and carrageenan-induced rat paw edema, decreased acetic acid-induced mouse vascular permeability and inhibited cotton pellet-induced rat granuloma formation.

CONCLUSION

Our finding indicates that taraxasterol has obvious in vivo anti-inflammatory effects against animal models. It will provide experimental evidences for the traditional use of Taraxacum officinale and taraxasterol in inflammatory diseases.

Prolonged course of hepatic granulomatous disease due to Bartonella henselae infection

Cat-scratch disease (CSD) is an emerging zoonosis caused by Bartonella henselae. The disease is usually self-limiting and typically presents in about 90% of all cases as a subacute regional lymphadenopathy. We present a case report of an unusual CSD presentation, persistent hepatic granulomatous disease due to Bartonella henselae infection despite combination therapy with doxycycline and rifampicin. Furthermore, a review of literature was conducted. (Acta gastroenterol. belg., 2016, 79, 497-499).

Metastatic Crohn disease clinically reminiscent of erythema nodosum on the right leg

Cutaneous manifestations are well-recognized complications of Crohn disease (CD) that can be divided into disease-specific and reactive conditions. One of the most common reactive conditions is erythema nodosum (EN), which presents as subcutaneous tender nodules most often on the legs. On the other hand, metastatic Crohn disease (MCD) is a rare cutaneous manifestation of CD defined as the presence of noncaseating granulomas that are not contiguous with the gastrointestinal (GI) tract. The clinical presentation of MCD is variable; however, lesions often are located on the legs and genital region. We report the case of a 21-year-old woman with a 6-year history of CD who presented with MCD clinically simulating EN.

A Case of Mediastimal Emphysema Possibly Caused by the Insertion of a Laryngoscope

Insertion of a laryngoscope to a patient with a strong pharyngeal reflex resulted in pharyngeal injury and subsequent development of mediastinal emphysema. An increase in airway pressure accompanying a strong pharyngeal reflex, as well as pharyngeal injury were thought to be factors associated with the development of mediastinal emphysema.

Caseating granulomas in cutaneous leishmaniasis

Background

Caseating granulomas are often associated with a mycobacterial infection (TB) and are thought to be exceedingly rare in cutaneous leishmaniasis (CL). However, no large series has accurately documented the incidence of caseating granulomas in CL.

Methods

A multiregional cohort consisting of 317 patients with CL [Syria (157), Pakistan (66), Lebanon (47), Saudi Arabia (43), Ethiopia (2) and Iran (2)] was reviewed. Clinical [age, sex, disease duration, lesion type and geographic and anatomic location] and microscopic data [presence of and type of granuloma, Ridley's parasitic index (PI) and pattern (RP)] were documented. Presence of microorganisms was evaluated using special stains (GMS, PAS, AFB and Gram) and polymerase chain reaction (PCR) for TB and CL. All cases included in this study were confirmed as CL by PCR followed by restriction fragment length polymorphism analysis for molecular speciation and were negative for other organisms by all other studies performed. Categorical and continuous factors were compared for granuloma types using Chi-square, t-test or Mann-Whitney test as appropriate.

Results

Granulomas were identified in 195 (61.5%) cases of CL and these were divided to 49 caseating (25.2%), 9 suppurative (4.6%) and 137 tuberculoid without necrosis (70.2%). Caseating and tuberculoid granuloma groups were significantly different in terms of the geographical source, with more cases harboring caseating granulomas in Saudi Arabia (p<0.0001). Histologically, both groups were also different in the distribution of their RP (p<0.0001) with a doubling RP3 in caseating granulomas (31% vs. 15%) as opposed to doubling of RP5 in tuberculoid granuloma group (38% vs. 19%). Time needed to achieve healing (RP5) was notably shorter in tuberculoid vs. caseating group (4.0 vs. 6.2 months). Parasitic Index, CL species and other considered variables did not differ for the granuloma type groups.

Conclusion

In our multiregional large cohort, a notable 18.2% of all CL cases harbored caseating granulomas therefore; CL should be considered part of the differential diagnosis for cases with caseating granulomas in endemic regions, especially considering that the regions included in our cohort are also endemic for TB. Of note, cases of CL with caseating granulomas also showed a slower healing process, with no association with specific species, which may be due to worse host immune response in such cases or to a more aggressive leishmania strains.

Cutaneous leishmaniasis displays a wide spectrum of clinical and microscopic findings. The microscopic manifestations have been categorized into five groups. The type of granulomatous response defined in group V is usually tuberculoid in nature with exceedingly rare cases described with necrotizing granulomas in contrast to cutaneous infections with tuberculosis and other mycobacteria that are typically associated with necrotic granulomas. The old world countries endemic for cutaneous leishmania also happen to be endemic for other granulomatous diseases such as leprosy, tuberculosis and cutaneous mycoses. The most common diagnostic approach used in these countries is still microscopic examination despite the advances in molecular diagnostic techniques and culture methods. We document an 18.2% incidence of caseating granulomas in cutaneous leishmania. Hence, cutaneous leishmania should be part of the differential diagnosis for cases with caseating granulomas in endemic regions in addition to other causative infections.

Sarcoidosis

Sarcoidosis is a systemic disease of unknown cause that is characterised by the formation of immune granulomas in various organs, mainly the lungs and the lymphatic system. Studies show that sarcoidosis might be the result of an exaggerated granulomatous reaction after exposure to unidentified antigens in individuals who are genetically susceptible. Several new insights have been made, particularly with regards to the diagnosis and care of some important manifestations of sarcoidosis. The indications for endobronchial ultrasound in diagnosis and for PET in the assessment of inflammatory activity are now better specified. Recognition of unexplained persistent disabling symptoms, fatigue, small-fibre neurological impairment, cognitive failure, and changes to health state and quality of life, has improved. Mortality in patients with sarcoidosis is higher than that of the general population, mainly due to pulmonary fibrosis. Predicted advances for the future are finding the cause of sarcoidosis, and the elucidation of relevant biomarkers, reliable endpoints, and new efficient treatments, particularly in patients with refractory sarcoidosis, lung fibrosis, and those with persistent disabling symptoms.

Immunohistological characterization of spinal TB granulomas from HIV-negative and -positive patients

Tuberculosis (TB) is mainly a disease of the lungs, but Mycobacterium tuberculosis (Mtb) can establish infection in virtually any organ in the body. Rising rates of extrapulmonary (EP) TB have been largely associated with the HIV epidemic, as patients co-infected with HIV show a four-fold higher risk of EPTB. Spinal TB (Pott's Disease), one of the most debilitating extrapulmonary forms of disease, is difficult to diagnose and can cause deformity and/or neurological deficits. This study examined the histopathology and distribution of immune cells within spinal TB lesions and the impact of HIV on pathogenesis. The overall structure of the spinal granulomas resembled that seen in lung lesions from patients with pulmonary TB. Evidence of efficient macrophage activation and differentiation were detectable within organized structures in the spinal tissue, irrespective of HIV status. Interestingly, the granulomatous architecture and macroscopic features were similar in all samples examined, despite a reversal in the ratio of infiltrating CD4 to CD8 T cells in the lesions from HIV-infected patients. This study provides a foundation to understand the mechanism of tissue destruction and disease progression in Spinal TB, enabling the future development of novel therapeutic strategies and diagnostic approaches for this devastating disease.

Extrapulmonary manifestations of sarcoidosis

Sarcoidosis is a systemic disease characterized by the development of epithelioid granulomas in various organs. Although the lungs are involved in most patients with sarcoidosis, virtually any organ can be affected. Recognition of extrapulmonary sarcoidosis requires awareness of the organs most commonly affected, such as the skin and the eyes, and vigilance for the most dangerous manifestations, such as cardiac and neurologic involvement. In this article, the common extrapulmonary manifestations of sarcoidosis are reviewed and organ-specific therapeutic considerations are discussed.

Bone marrow biopsy findings in brucellosis patients with hematologic abnormalities

BACKGROUND

Brucellosis can mimic various multisytem diseases, showing wide clinical polymorphism that frequently leads to misdiagnosis and treatment delay, further increasing the complication rates. In this study, we aimed to examine bone marrow biopsy findings in brucellosis cases presenting with hematologic abnormalities.

METHODS

Forty-eight brucellosis cases were prospectively investigated. Complaints and physical examination findings of patients were recorded. Patients' complete blood count, routine biochemical tests, erythrocyte sedimentation rate, C-reactive protein and serological screenings were performed. Bone marrow biopsy and aspiration was performed in patients with cytopenia, for bone marrow examination and brucella culture, in accordance with the standard procedures from spina iliaca posterior superior region of pelvic bone.

RESULTS

Of the 48 patients, 35 (73%) were female and 13 (27%) were male. Mean age was (34.8 ± 15.4) years (age range: 15 - 70 years). Anemia, leukopenia, thrombocytopenia and pancytopenia were found in 39 (81%), 28 (58%), 22 (46%) and 10 patients (21%), respectively. In the examination of bone marrow, hypercellularity was found in 35 (73%) patients. Increased megacariocytic, erythroid and granulocytic series were found in 28 (58%), 15 (31%) and 5 (10%) patients, respectively. In addition, hemophagocytosis was observed in 15 (31%) patients, granuloma observed in 12 (25%) and increased eosinophil and plasma cells observed in 9 (19%) patients.

CONCLUSION

According to the results of our series, hemophagocytosis, microgranuloma formation and hypersplenism may be responsible for hematologic complications of brucellosis.

On the missing link between inflammation and cancer

A various array of cutaneous granulomatous disorders have been found to be associated with internal malignancy. Among them, sarcoidosis, granuloma anulare (GA), psoriasis, pyoderma gangrenosum (PG), or other neutrophilic dermatoses such as the Sweet syndrome and subcorneal pustular dermatosis may precede the development of a neoplastic process by months or years. Pathogenic links of inflammation with cancer are discussed, including inflammation, intrinsic immune dysfunction, cytokines and interleukins, angiogenetic factors, and epigenetic changes.

Induction of ER stress in macrophages of tuberculosis granulomas

Background

The endoplasmic reticulum (ER) stress pathway known as the Unfolded Protein Response (UPR) is an adaptive survival pathway that protects cells from the buildup of misfolded proteins, but under certain circumstances it can lead to apoptosis. ER stress has been causally associated with macrophage apoptosis in advanced atherosclerosis of mice and humans. Because atherosclerosis shares certain features with tuberculosis (TB) with regard to lesional macrophage accumulation, foam cell formation, and apoptosis, we investigated if the ER stress pathway is activated during TB infection.

Principal Findings

Here we show that ER stress markers such as C/EBP homologous protein (CHOP; also known as GADD153), phosphorylated inositol-requiring enzyme 1 alpha (Ire1α) and eukaryotic initiation factor 2 alpha (eIF2α), and activating transcription factor 3 (ATF3) are expressed in macrophage-rich areas of granulomas in lungs of mice infected with virulent Mycobacterium tuberculosis (Mtb). These areas were also positive for numerous apoptotic cells as assayed by TUNEL. Microarray analysis of human caseous TB granulomas isolated by laser capture microdissection reveal that 73% of genes involved in the UPR are upregulated at the mRNA transcript level. The expression of two ER stress markers, ATF3 and CHOP, were also increased in macrophages of human TB granulomas when assayed by immunohistochemistry. CHOP has been causally associated with ER stress-induced macrophage apoptosis. We found that apoptosis was more abundant in granulomas as compared to non-granulomatous tissue isolated from patients with pulmonary TB, and apoptosis correlated with CHOP expression in areas surrounding the centralized areas of caseation.

Conclusions

In summary, ER stress is induced in macrophages of TB granulomas in areas where apoptotic cells accumulate in mice and humans. Although macrophage apoptosis is generally thought to be beneficial in initially protecting the host from Mtb infection, death of infected macrophages in advanced granulomas might favor dissemination of the bacteria. Therefore future work is needed to determine if ER-stress is causative for apoptosis and plays a role in the host response to infection.

Contribution of TIR domain-containing adapter inducing IFN-beta-mediated IL-18 release to LPS-induced liver injury in mice

BACKGROUND/AIMS

After treatment with heat-killed Propionibacterium acnes mice show dense hepatic granuloma formation. Such mice develop liver injury in an interleukin (IL)-18-dependent manner after challenge with a sublethal dose LPS. As previously shown, LPS-stimulated Kupffer cells secrete IL-18 depending on caspase-1 and Toll-like receptor (TLR)-4 but independently of its signal adaptor myeloid differentiation factor 88 (MyD88), suggesting importance of another signal adaptor TIR domain-containing adapter inducing IFN-beta (TRIF). Nalp3 inflammasome reportedly controls caspase-1 activation. Here we investigated the roles of MyD88 and TRIF in P. acnes-induced hepatic granuloma formation and LPS-induced caspase-1 activation for IL-18 release.

METHODS

Mice were sequentially treated with P. acnes and LPS, and their serum IL-18 levels and liver injuries were determined by ELISA and ALT/AST measurement, respectively. Active caspase-1 in LPS-stimulated Kupffer cells was determined by Western blotting.

RESULTS

Macrophage-ablated mice lacked P. acnes-induced hepatic granuloma formation and LPS-induced serum IL-18 elevation and liver injury. Myd88(-/-) Kupffer cells, but not Trif(-/-) cells, exhibited normal caspase-1 activation upon TLR4 engagement in vitro. Myd88(-/-) mice failed to develop hepatic granulomas after P. acnes treatment and liver injury induced by LPS challenge. In contrast, Trif(-/-) mice normally formed the hepatic granulomas, but could not release IL-18 or develop the liver injury. Nalp3(-/-) mice showed the same phenotypes of Trif(-/-) mice.

CONCLUSIONS

Propionibacterium acnes treatment MyD88-dependently induced hepatic granuloma formation. Subsequent LPS TRIF-dependently activated caspase-1 via Nalp3 inflammasome and induced IL-18 release, eventually leading to the liver injury.

[Physiopathology of sarcoidosis]

Sarcoidosis results from an uncontrolled cell-mediated immune reaction involving activated T cells and monocytes-macrophages, characterized by the formation of typical granulomas at the sites of the lesions. The interactions between both cell types induce the release of several mediators that play a central role in the development of granulomas, allowing to design new therapies. The aetiology of sarcoidosis remains unknown, but the disease is currently viewed as the consequence of a chronic immunological response associating a genetic susceptibility and specific environmental factors.

[Granulomatous disease in common variable immunodeficiency]

PURPOSE

Common variable immunodeficiency (CVID), defined by defective production of immunoglobulins, is the most common primary immunodeficiency in adulthood requiring a medical follow-up. Repeated bacterial infections and/or autoimmune manifestations and/or benign lymphoproliferation (including follicular hyperplasia and/or granulomatous disease) are the hallmark of the disease. This review aims at describing recent advances in the understanding and treatment of granulomatous disease in CVID.

CURRENT KNOWLEDGE AND KEY POINTS

Clinical features of granulomatous disease in CVID can mimic sarcoidosis, remarkable by the low levels of circulating immunoglobulins. Granulomas may be found in several organs in a single patient, and the main features are pulmonary, lymphoid, cutaneous, hepatic or splenic. The features of CVID is remarkable by the high frequency of autoimmune diseases complicating the immunodeficiency. Some immunological abnormalities have been described in such patients, including lymphopenia, decreased T-cells proliferations to mitogens and antigens. Rare polymorphisms in the gene encoding TNFalpha (Tumor Necrosis Factor) have been identified in CVID patients with granulomatous disease.

FUTURE PROSPECTS AND PROJECTS

The evolution of the disease is severe, particularly when the lung is involved. Treatment consists in immunoglobulins substitution, immunosuppressive agents (corticosteroids, cyclophosphamide) and anti-TNFalpha antibodies. These treatments are difficult to manage in such immunocompromised patients.

Laryngopharyngeal Abnormalities in Hospitalized Patients With Dysphagia

OBJECTIVES

To determine the prevalence of laryngopharyngeal (LP) abnormalities in hospitalized patients with dysphagia referred for flexible endoscopic evaluation of swallowing (FEES).

STUDY DESIGN

Retrospective, blinded review by two otolaryngologists of 100 consecutive FEES studies performed and video-recorded by a speech-language pathologist (SLP).

METHODS

Two otolaryngologists reviewed videos of 100 consecutive FEES studies on hospitalized patients with dysphagia for the presence of abnormal LP findings.

RESULTS

Sixty-one male and 38 female patients comprised the hospital dysphagia cohort. The mean age was 62. One subject could not be evaluated because of the severity of the retained secretions, leaving 99 subjects in the cohort. Seventy-six percent had been previously intubated, with a mean intubation duration of 13 days. The overall prevalence of abnormal LP findings was 79%. Forty-five percent of the patients presented with two or more findings, which included arytenoid edema (33%), granuloma (31%), vocal fold paresis (24%), mucosal lesions (17%), vocal fold bowing (14%), diffuse edema (11%), airway stenosis (3%), and ulcer (6%). There was a significant difference in LP findings between those individuals who had or had not been intubated.

CONCLUSIONS

Hospitalized patients with dysphagia are at high risk for LP abnormalities, particularly if they have been intubated, and may benefit from either 1) an initial joint examination by the SLP and otolaryngologist or 2) an otolaryngologist's review of the recorded examination conducted by the SLP. Such otolaryngology involvement could identify airway stenosis patients at an earlier stage, initiate granuloma treatment sooner, enable earlier biopsy of unexpected lesions, and allow follow-up of mucosal and neuromuscular findings that do not respond to medical management.

Dealcoholized red and white wines decrease oxidative stress associated with inflammation in rats

In vitroexperiments have demonstrated that polyphenols exhibit antioxidant and anti-inflammatory activities. The present study was designed to test whether dealcoholized red (DRW) and white (DWW) wines can decrease the oxidative stress associated with inflammationin vivo. Rats were fed for 15 d either a control diet or one supplemented with DRW or DWW. Finally, a granuloma was induced by subcutaneous administration of carrageenan. Although DRW showed higher antioxidant activityin vitrothan DWW, both wines decreased the number of cells recruited into the granuloma pouch. Malondialdehyde decreased in plasma and inflammatory exudate from rats fed with DRW- and DWW-rich diets. Moreover, the concentration of NO increased in exudate, which correlates with the increase in the citrulline:arginine ratio. Polymorphonuclear leucocytes from the inflammatory exudate of rats fed dealcoholized wines showed decreased superoxide anion (O2∙−) production and increased NO productionex vivo. This change in NO production resulted from increased expression and activity of inducible NO synthase (EC 1.14.13.39). Moreover, the up regulation of cyclo-oxygenase-2 (EC 1.14.99.1) protein expression observed in rats fed the DRW-rich diet was not related to a direct effect of NO. The present results indicate that the non-alcoholic compounds of wines not only improve antioxidant status in an inflammatory situation, but also limit cell infiltration, possibly through a decrease in O2∙−and an increase in NO production.

Sarcoidosis of the nervous system

Although sarcoidosis is rarely confined to the nervous system, any neurological features that do occur frequently happen early in the course of the disease. The most common neurological presentation is with cranial neuropathies, but seizures, chronic meningitis and the effects of mass lesions are also frequent. The diagnostic process should first confirm nervous system involvement and then provide supportive evidence for the underlying disease; in the absence of any positive tissue biopsy, the most useful diagnostic tests are gadolinium enhanced MRI of the brain and CSF analysis, although both are non-specific. The mainstay of treatment is corticosteroids, but these often have to be combined with other immunosuppressants such as methotrexate, hydroxychloroquine or cyclophosphamide. There is increasing evidence that infliximab is a safe treatment with good steroid sparing capacity.

Xanthogranulomatous cholecystitis expressing high levels of DUPAN-II

We report a case of xanthogranulomatous cholecystitis (XGC) showing high levels of serum DUPAN-II in a 65-year-old woman. Preoperative radiologic examination showed no abnormal findings except in the gallbladder. Endoscopic ultrasonography was effective for differentiating chronic cholecystitis from gallbladder cancer before the operation. Cholecystectomy was performed by laparotomy, and the diagnosis of XGC was confirmed intraoperatively by examining a frozen section. Histologically, no cancer lesion was observed in the gallbladder, while immunochemical reactivity to DUPAN-II was demonstrated in the brush-border area of the epithelium and in histiocytes in the gallbladder. The half-life of serum DUPAN-II in our patient after cholecystectomy was approximately 1 month, and finally dropped to within the normal range after cholecystectomy.

Granulomatous hypophysitis: presentation and MRI appearance

Granulomatous hypophysitis (GrHy) is a relatively rare inflammatory disease compared with lymphocytic hypophysitis. Only a few cases with magnetic resonance imaging (MRI) findings have been reported to date. We describe the MRI findings for two patients with GrHy with unusual histories and clinical outcomes.

Postoperative granuloma after stapedectomy: is it destiny or avoidable?

OBJECTIVE

The aims of this study were (1) to investigate the pathophysiological characteristics of the middle ear mucoperiosteum against the caustic nature of the gastric content (GC), which consists largely of acid and pepsin components, and (2) to investigate the possible role of gastroesophageal reflux and postoperative vomiting (POV) in the etiology of poststapedectomy granuloma.

METHODS

40 Spraque-Dawley rats of either sex and with a body weight of 200-300 g were used, and divided into different study groups: group 1: GC administration to the middle ear (n = 8); group 2: phosphate-buffered saline administration to the middle ear (n = 8); group 3: GC (pH: 2) administration in the presence of a Teflon piston (TP) (n = 6); group 4: phosphate-buffered saline administration in the presence of a TP (n = 6); group 5: GC administration in the presence of a wired piston (WP) (n = 6); group 6: phosphate- buffered saline administration in the presence of a WP (n = 6). GC was administrated to the middle ear cavities by way of the eustachian tube (ET). In order to overcome the pressure of the ET, a pump mechanism was used. The increased nasopharyngeal pressure caused a passive opening of the ET, and transferred a bolus to the middle ear. The animals were decapitated after 1 week, and the bullae were isolated. The tympanic bullae were serially cut and examined with light microscopy.

RESULTS

In the saline controls, there was only a mild amount of polymorphonuclear cell (PMN) infiltration in the mildly thickened subepithelial space, indicating a less pronounced inflammation as compared to the gastric acid group. In the GC group, in addition to focal hemorrhage and severe subepithelial infiltration of PMNs, the middle ear mucosa was dramatically thickened with subepithelial edema and dilated capillaries. In the subepithelial tissue, retention cysts and granulation tissue were present. In the piston groups (TP and WP), there was extensive subepithelial inflammation and edema after GC and saline administrations. Granulation tissue filling the entire bulla around the piston segments was detected.

CONCLUSION

The relationship between the administration of GC and middle ear inflammation, and the possible role of POV in the etiology of poststapedectomy granuloma are emphasized with our experimental study. The length of the TP may be considerably important to prevent POV which may lead to gastric reflux to the middle ear.

An in vitro model of the leukocyte interactions associated with granuloma formation in Mycobacterium tuberculosis infection

The principal defense of the human host against a Mycobacterium tuberculosis infection is the formation of granulomas, organized collections of activated macrophages, including epithelioid and multinucleated giant cells, surrounded by lymphocytes. This granuloma can sequester and contain the bacteria preventing active disease, and if the granuloma is maintained, these bacteria may remain latent for a person's lifetime. Secretion of a variety of chemoattractant cytokines following phagocytosis of the bacilli by the macrophage is critical not only to the formation of the granuloma but also to its maintenance. To investigate this process of early granuloma formation, we developed an in vitro model composed entirely of human cells. Combining blood lymphocytes and autologous macrophages from healthy purified protein derivative skin test-negative individuals and mycobacteria resulted in the formation of small, rounded aggregate structures. Microscopic examination found macrophage-specific CD68(+) epithelioid macrophages and small round CD3(+) lymphocytes that in complex resembled small granulomas seen in clinical pathology specimens. Acid-fast staining bacteria were observed between and possibly within the cells composing the granulomas. Supernatants from the infected cells collected at 24 and 48 h and 5 and 9 days after infection were analyzed by a multiplexed cytokine bead-based assay using the Luminex 100 and were found to contain interleukin (IL)-6, IL-8, interferon-gamma and tumor necrosis factor-alpha, cytokines known to be involved in human granuloma formation, in quantities from two-fold to 7000-fold higher than supernatants from uninfected control cells. In addition, chemotaxis assays demonstrated that the same supernatants attracted significantly more human peripheral blood mononuclear cells than those of uninfected cells (P<0.001). This model may provide insight into the earliest stages of granuloma formation in those newly infected.

Immunopathology of schistosomiasis

Waterborne parasitic diseases plague tropical regions of the world with the development of water resources often increasing transmission. Skin-penetrating cercariae (infectious stages of schistosome parasites) mature within their mammalian host, form sexual pairs and produce several hundred eggs per day. Many eggs are swept within the circulation and in the case of Schistosoma mansoni and S. japonicum, become lodged within hepatic sinusoids, invoking a fibrotic granulomatous response. Animal studies have identified a moderate type 1 helper (Th1) response to parasite antigens; however, a robust Th2 response to egg-derived antigens dominates and propagates fibrogenesis within the liver. Elegant T helper cell polarization studies have highlighted that critical control of Th1, Th2 and interleukin (IL)-17-secreting lymphocytes is necessary to prevent severe liver pathology. Alternatively activated macrophages develop in the Th2 milieu and upregulate Fizz1, Ym-1 and Arg-1. The possible contribution of macrophages to fibrogenesis and their role in immune regulation are discussed. Within the liver, natural (CD4(+)CD25(+) Forkhead box protein 3 (Foxp3)(+)) and inducible (CD4(+)Foxp3(-)) Treg's are recruited, providing an essential regulatory arm to stabilize the immune response and limit immunopathology. This review ties together current thinking of how the granulomatous response develops, causing much of the associated immunopathology, with extensive discussions on how regulatory cells and cytokine decoy receptors serve to limit the extent of immune-mediated pathology during schistosomiasis.

Neurosarcoïdose : état des connaissances

The origins of neurosarcoidosis, a multisystemic granulomatous disease, remain unknown. Nervous system localizations remain rare, but severe. Lymphocytic meningitis, psychiatric disorders, diabetes insipidus and cranial nerve palsy are the most frequent signs. Cerebral fluid test and cervical medullar and cerebral MRI with gadolinium have to be performed first. In some cases, histological evidence of granuloma have to be obtained with neuromuscular, meningeal or cerebral biopsies. Functional impairment and life-threatening conditions require early corticosteroid therapy. In worsening cases or in the event of no therapeutic response or poor tolerance to corticosteroids, other immunosuppressive agents should be associated. Maintenance therapy and most often life long maintenance therapy allow a continuous success while avoiding relapse.

Cytopathogenicity of Balamuthia mandrillaris, an Opportunistic Causative Agent of Granulomatous Amebic Encephalitis

Balamuthia mandrillaris is a free-living ameba and an opportunistic agent of lethal granulomatous amebic encephalitis in humans and other mammals. Balamuthia mandrillaris is highly cytopathic but, in contrast to the related Acanthamoeba, does not feed on bacteria and seems to feed only on eukaryotic cells instead. Most likely, the cytopathogenicity of B. mandrillaris is inseparable from its infectivity and pathogenicity. To better understand the mechanisms of B. mandrillaris cytopathogenicity, an assay for measuring amebic cytolytic activity was adapted that is based on the release of a reporter enzyme by damaged target cells. The ameba is shown to lyse murine mastocytoma cells very efficiently in a time- and dose-related manner. Furthermore, experiments involving semipermeable membranes and phagocytosis inhibitors indicate that the cytolytic activity of B. mandrillaris is essentially cell contact-dependent. Standard and fluorescence light microscopy, as well as scanning and transmission electron microscopy support and extend these findings at the ultrastructural level.

Sarcoidosis presenting with hearing loss and granulomatous interstitial nephritis in an adolescent

Granulomatous interstitial nephritis is an uncommon finding in a kidney biopsy. The differential diagnosis is broad and includes infections, drug exposure, and sarcoidosis. Sarcoidosis, a systemic disorder of unknown etiology characterized by the presence of noncaseating granulomata in affected organs, is rare in children. We discuss an adolescent boy with the unusual presentation of granulomatous interstitial nephritis and acute deafness. Sarcoidosis should be considered as part of the differential diagnosis for children and adolescents with hearing loss and kidney disease.

PROINFLAMMATORY CYTOKINES IN GRANULOMAS ASSOCIATED WITH MURINE CYSTICERCOSIS ARE NOT THE CAUSE OF SEIZURES

Neurocysticercosis is a parasitic infection of the human central nervous system caused by the cestode Taenia solium. The most common clinical manifestations of neurocysticercosis are seizures. Taenia crassiceps cysticercosis in mice has been used as an experimental model for T. solium cysticercosis. Granulomas surrounding murine cysticerci have striking immunopathological resemblance to human neurocysticercosis; early stage granulomas were able to induce seizures in a rodent model. To assess the role of proinflammatory cytokines in early stage granulomas, we isolated RNA from murine cysticercal granulomas and checked for cytokine expression by reverse transcriptase-polymerase chain reaction (RT-PCR) and/or ribonuclease (RNase) protection assays. Cytokine expression was compared with histological stages. Interleukin (IL)-1alpha, IL-1beta, IL-1 receptor antagonist, and tumor necrosis factor (TNF-alpha) were the major cytokines detected in all granulomas. Signals for IL-12, IL-18, and IL-6 RNA were not consistently detected and, when detected, were barely demonstrable. Expression of migration inhibitory factor (MIF), IL-6, IL-1alpha, TNF-alpha, and IL-18 was not significantly different between early and late-stage granulomas. Expression of IL-1beta, IL-1 receptor antagonist, and IL-12 p40 were higher in late, compared with early, stages. Thus, we demonstrated a broad range of cytokines in these granulomas. However, we did not document preferential expression of any proinflammatory cytokines in early stage granulomas. Thus, proinflammatory cytokines are not responsible for the seizures in the rodent model of neurocysticercosis.

Social isolation and the inflammatory response: sex differences in the enduring effects of a prior stressor

Numerous epidemiological studies have demonstrated an association between persistent social isolation and “all-cause” morbidity and mortality. To date, no causal mechanism for these findings has been established. Whereas animal studies have often reported short-term effects of social isolation on biological systems, the long-term effects of this adverse psychological state have been understudied. This is the first animal study to examine the effects of long-term social isolation from weaning through young adulthood on an innate inflammatory response linked to numerous disease processes. Results presented here offer a plausible link between vulnerability to disease and social neglect. For socially isolated male and female Sprague-Dawley rats, a naturally gregarious species, formation of a granuloma in response to a subcutaneous injection of carrageenin (seaweed) was significantly delayed compared with the response of animals housed in single-sex groups of five. Significant sex differences, however, emerged when an acute prior stressor was superimposed on the experience of chronic social isolation. In this context, isolated females produced a more robust inflammatory response than isolated males. This sexual dimorphism at the nexus of chronic social isolation, acute stress, and inflammatory processes may account for the observation in humans that men with low levels of social integration are more vulnerable to disease and death than women.

Granulomatous disease in common variable immunodeficiency

Common variable immunodeficiency (CVID) is a primary immunodeficiency of unknown etiology characterized by low levels of immunoglobulin (Ig)G, failure to make specific antibodies in response to infection or immunization, and variable T-cell abnormalities. Multisystemic granulomatous disease is a well-documented complication of CVID, and its presence is associated with significant morbidity and early mortality. Although the lung is the most common organ system affected, granulomas are also found frequently in other organs, including skin, liver, spleen, and the gastrointestinal tract. Autoimmune disorders are common in these patients, and there appears to be an increased propensity to develop lymphoproliferative disorders. Common physical, radiographic, and laboratory abnormalities in patients with CVID and granulomatous disease include splenomegaly, hilar and mediastinal lymphadenopathy with ground glass or nodular opacities in the lung parenchyma, and reduced T-cell numbers and function. The etiology of granulomatous disease in patients with CVID is unknown, and optimal treatment of granulomatous disease in CVID remains to be established. Further studies are needed to elucidate the underlying etiology of granulomatous lymphoproliferative interstitial lung disease and to delineate appropriate treatments for this disease.

Validity and Reliability of the Glottal Function Index

OBJECTIVE

To evaluate a symptom-focused vocal impairment instrument for the evaluation of patients with voice disorders.

DESIGN

Prospective, nonrandomized study of patients with voice disorders undergoing treatment with validation of a new symptom index, the Glottal Function Index (GFI).

SETTING

Voice disorders clinic at an academic tertiary care hospital.

PATIENTS

Consecutive patients undergoing therapy for glottal insufficiency, adductor spasmodic dysphonia, nodules, and granuloma (40 patients in each group) and 40 control patients.

INTERVENTIONS

The Pearson correlation coefficient was used to evaluate GFI reproducibility and to compare it with the Voice Handicap Index (VHI). The paired-samples t test was used to compare pretherapy and posttherapy GFI values.

MAIN OUTCOME MEASURES

Correlation of GFI with VHI; comparison of the GFI in normals, and in pretherapy and posttherapy GFI and VHI scores.

RESULTS

The mean +/- SD normative GFI score was 0.87 +/- 1.32. The correlation coefficient for GFI between independent pretherapy measurements was 0.56 (P<.001). The correlation coefficient between total GFI and total VHI scores was 0.61 (P<.001). The mean posttherapy GFI scores improved among all groups as follows: glottal insufficiency: presenting GFI score, 12.7 +/- 4.1; posttherapy GFI score, 6.8 +/- 5.4; nodules: presenting GFI score, 12.9 +/- 4.2; posttherapy GFI score, 8.9 +/- 4.6; adductor spasmodic dysphonia: presenting GFI score, 13.2 +/- 4.1; posttherapy GFI score, 8.9 +/- 4.9; and granuloma: presenting GFI score, 7.8 +/- 4.6; posttherapy GFI score, 3.8 +/- 2.1. Relative to controls, the GFI score at presentation was significantly elevated and demonstrated significant reduction following treatment across each of these entities (P<.05).

CONCLUSIONS

The GFI is a reliable, reproducible, 4-item, self-administered symptom index with excellent criterion-based and construct validity. Its advantages over existing indexes include brevity and ease of administration. The GFI is a useful adjunct in the evaluation and treatment of patients with glottal dysfunction.

Inhibition of granuloma-associated angiogenesis by controlling mast cell mediator release: role of mast cell protease-5

We investigated the role of mast cells in granuloma-associated angiogenesis in rat by using: (i) a mast cell membrane stabilizer, ketotifen; (ii) a mast cell depleting agent, compound 48/80. Moreover, we focused on the role of chymases, which exhibit proinflammatory and pro-angiogenic properties by using: (i) chymostatin, an inhibitor of chymase activity; (ii) a specific antisense oligonucleotide (AS-ODN) designed against rat mast cell protease-5 (rMCP-5), the most abundantly expressed chymase in the skin. The formation of granuloma was evaluated, as wet weight, 96 h after the subcutaneous implant of two lambda-carrageenin (1%)-soaked sponges on the back of male Wistar rats. Angiogenesis was evaluated as haemoglobin content in the granulomatous tissue and as level of tumour necrosis factor-alpha (TNF-alpha) in the exudates. A single injection of ketotifen (1-5-25 mg kg(-1) i.p.) significantly reduced granuloma formation by 31.6, 44.6 and 71.9%, and haemoglobin content by 17.0, 35.0 and 66.2%, suggesting that the release of mediator(s) from mast cells modulates the process. Chymostatin (5-10 nmol(-1) site(-1) day(-1)) reduced granuloma-associated angiogenesis by 57.3 and 70.0%. RT-PCR analysis showed that rMCP-5 mRNA amounts were significantly reduced by rMCP-5 AS-ODN (1.25-2.5-5.0 nmol site(-1)) by 69.5, 72.5 and 81.8%. In parallel experiments, rMCP-5 AS-ODN (1.25, 2.5, 5.0 nmol site(-1)) strongly reduced granuloma weight (26.1, 45.0 and 56.3%) and haemoglobin content (22.2, 50.4, 62.03%), suggesting that the observed effect is mediated through an antisense mechanism. In conclusion, these data suggest that: (i) inhibition of mast cell mediators release may represent a novel strategy to modulate angiogenesis; (ii) among the chymase family, rMCP-5 is a key promoter of angiogenesis in the rat.

Growth hormone reduces the severity of fibrosis associated with chronic intestinal inflammation

BACKGROUND & AIMS

Growth hormone (GH) is used to treat growth delay in children with Crohn's disease and in patients with short-bowel syndrome. GH can increase collagen accumulation in intestinal mesenchymal cells, raising concern that GH therapy could exacerbate fibrosis in patients with Crohn's disease. We tested if GH treatment altered inflammation or fibrosis during chronic, experimental granulomatous enterocolitis.

METHODS

Ileum and cecum of Lewis rats were subserosally injected with peptidoglycan-polysaccharide (PG-APS) or control human serum albumin. At the onset of chronic PG-APS-induced inflammation, rats were administered recombinant human GH or vehicle for 14 days. Fibrosis and inflammation were quantified by gross gut disease scoring, histologic scoring, type I collagen, and cytokine expression in cecum. Abundance and localization of suppressor of cytokine signaling-3 (SOCS-3) messenger RNA and/or protein were determined in cecum. Effect of GH, cytokines, or PG-APS on SOCS-3 synthesis was measured in intestinal myofibroblasts. Myofibroblasts overexpressing SOCS-3 were used to test whether SOCS-3 inhibits collagen accumulation.

RESULTS

In PG-APS-injected rats, GH modestly reduced gross adhesions and mesenteric contractions, cecal fibrosis score, and collagen expression, but had no effect on intestinal inflammation. GH increased SOCS-3 messenger RNA and protein abundance in PG-APS rats and SOCS-3 messenger RNA was localized to the periphery of granulomas. GH in combination with cytokines or PG-APS, but not alone, induced SOCS-3 synthesis in intestinal myofibroblasts. Myofibroblasts overexpressing SOCS-3 showed reduced cytokine-induced collagen accumulation.

CONCLUSIONS

GH modestly reduces intestinal fibrosis associated with chronic experimental enterocolitis and stimulates expression of antifibrogenic SOCS-3, suggesting that GH therapy in inflammatory bowel disease should not exacerbate fibrosis.

Xanthogranulomatous sialadenitis: a case report and literature review

Xanthogranulomatous tissue reaction is an uncommon but well-documented process that occurs at many sites in the body. It is most often recognized in the kidney and gallbladder, where its etiology is believed to involve an outflow obstruction. We report the case of a man with a parotid mass that exhibited features consistent with an inflammatory process on fine-needle aspiration biopsy. The mass persisted despite medical management, and the patient subsequently underwent a superficial parotidectomy. Histologic examination of the resected specimen identified a xanthogranulomatous tissue reaction adjacent to a Warthin's tumor. We compare the features of this case with those of the 2 previously reported cases of xanthogranulomatous sialadenitis, and we discuss its possible etiologies.

The HRCT appearances of granulomatous pulmonary disease in common variable immune deficiency

Approximately 10% of patients with common variable immune deficiency have systemic granulomatous disease with associated interstitial lung disease. From a population of patients with CVID attending a large tertiary referral clinic for primary immunodeficiency diseases we selected a cohort who had a restrictive defect or impaired gas transfer on pulmonary function testing and/or histologically proven granulomatous disease. HRCT scans of the thorax were reviewed retrospectively in 18 patients by two radiologists. Thirteen patients had diffuse reticulation, which varied from fine to coarse with features of fibrosis. Nodules were found in eight patients. In seven, these were associated with reticulation and in one they were an isolated finding. Bronchiectasis was found as the only abnormality in three and in addition to diffuse reticulation or nodules in another three patients. Greater appreciation of the spectrum of the radiological abnormalities in CVID patients with interstitial lung disease is important. Deteriorating lung function in patients with granulomatous CVID may be secondary to interstitial lung disease rather than bronchiectasis, and treatment should be tailored accordingly.

C and CX3C chemokines: cell sources and physiopathological implications

Within the fascinating world of chemokines, C and CX3C chemokines have long been regarded as two minor components, even though they present unique features and show less redundancy than the other chemokine families. Nevertheless, the body of data on their expression and role in various inflammatory disorders has grown in the past few years. The C chemokine family is represented by two chemokines, XCL1/lymphotactin-alpha and XCL2/lymphotactin-beta, whereas the CX3C chemokine family contains only one member, called CX3CL1/ fractalkine. In this review, we present an overview on the structure, expression and signaling properties of these chemokines and their respective receptors and examine how they contribute to inflammation and the regulation of leukocyte trafficking, as well as their potential role in the pathophysiology of human inflammatory diseases. Taken together, these data expand the biological importance of C and CX3C chemokines from that of simple immune modulators to a much broader biological role, even though their precise commitment within the framework of immune responses has still to be determined.

Effects of voice therapy on vocal process granuloma: a phonoscopic approach

PURPOSE

This study reviewed the effects of a voice therapy program in patients who had failed other treatments for vocal process granuloma related to laryngopharyngeal reflux. The program was offered to 16 patients, all of whom demonstrated contact of the vocal processes at the site of pathology on voicing. During an initial evaluation, each patient was counseled regarding the need for voice conservation and improved vocal hygiene. Of the 16 patients, 10 agreed to undergo voice therapy and were subsequently enrolled in the treatment program.

METHODS

The primary therapy objective was to modify each patient's vocal fold contact pattern so that a small gap remained between the vocal processes during voicing. A "phonoscopic" approach to therapy was used. That is, the clinician and the patient were able to observe the larynx endoscopically while also listening to the voice. This combined aural and visual approach enabled the clinician to guide the patient toward the treatment objective with precision and provided patients with immediate feedback regarding their progress.

RESULTS

Of the 10 patients who underwent therapy, 8 were able to achieve the treatment objective, and all 8 experienced resolution of pathology or a marked reduction in its extent. Six patients who did not undergo treatment, and the 2 who were unable to achieve the treatment objective, demonstrated minimal or no improvement, or worsening of their pathology, over the same period.

CONCLUSIONS

The treatment program described may be of value to similar patients with resistant granuloma related to extraesophageal reflux.

A case of isolated tuberculoid leprosy of antebrachial medial cutaneous nerve

Leprosy is an infectious disease of prevalence still high in endemic areas in Brazil. The neurological presentation depends on the involved nerve and is usually associated with skin lesions and the formation of multiple abscesses. We present a case of isolated tuberculoid leprosy, discuss the occurrence, the differential diagnosis and the treatment of this rare presentation and reaffirm the importance of considering leprosy in the differential diagnosis of patients with polyneuropathy or nerve enlargement with no skin lesions.

Pathological study of bronchospasms/tracheomalasia in patients with severe motor and intellectual disabilities

This report concerns two autopsy cases of severe motor and intellectual disabilities (SMID) who died of bronchospasms or tracheomalasia. One case had no anatomical change in the tracheal wall except for an endotracheal granuloma, while the other showed softening of the tracheal wall. Since patients with SMID have risk factors for bronchospasms and tracheomalasia, such as gastro-esophageal reflux, aspiration, and thoracic deformities, it is important that we suspect the possibility of these conditions, when we see the respiratory distress in cases of SMID.

[The role of vitamin D in the formation of granuloma and in calcium metabolism]

INTRODUCTION

Affection of the abdominal organs with sarcoidosis is a part of the generalized granulomatous diseases with clinical manifestations that vary depending on the affected organ.

IMMUNOPATHOGENESIS OF GRANULOMA AND THE ROLE OF VITAMIN D

Formation of granuloma represents a response of the host immune system to different antigen stimuli and it represents an attempt of the host to block the endogenous or exogenous irritant. The active form of vitamin D-1,25-dihydroxyvitamin-D (1,25-D) has an important function in formation of granuloma.

HEPATOMEGALY AND SPLENOMEGALY

As for the abdominal region, sarcoidosis is most frequently clinically manifested by liver and/or spleen enlargement (20-30% of the affected patients). However, granulomatous infiltrations may also be present along with normal sized organs. Other abdominal localizations are significantly less frequent.

THE ROLE OF VITAMIN D IN CALCIUM METABOLISM

Calcium metabolism disorder represents a significant problem in patients affected with sarcoidosis, particularly in extrapulmonary, chronic forms of the disease. It develops as a result of complex metabolic processes consequential to increased level of 1,25-D and it is considered to be a parameter of granuloma activity (physiological blood value is up to 45 pq/ml). An increased level of provitamin D initiates osteoclast activity that causes bone resorption, which represents a factor of osteoporosis that results in hypercalcemia and hypercalciuria.

RENAL CALCULOSIS AS A SIGN OF SARCOIDOSIS ACTIVITY

Increased calcium release into blood results in production of calcium deposits in the soft tissues and certain organs and thus calculosis develops. It is clinically most frequently manifested as renal calculosis, which is approximately 20 times more frequent in patients affected with sarcoidosis in comparison to general population.

CONCLUSION

Examinations of abdominal organ involvement should be a standard procedure in each patient affected with sarcoidosis.

The immunobiology of Th1 polarization in high-pathology schistosomiasis

Schistosomiasis is a serious global helminthic disease, in which the main immunopathology consists of a granulomatous and fibrosing reaction against tissue-trapped parasite eggs. The severity of this inflammatory process, the product of a CD4(+) T-cell-mediated immune response against parasite egg antigens, is, however, markedly uneven, both in human patients and among mouse strains in an experimental model. Severe schistosomiasis is associated with persistently elevated pro-inflammatory T-helper-1 (Th1)-type cytokines, whereas milder pathology is present when Th2 cytokines dominate. This scenario is supported by the pronounced pathology resulting from the obliteration of pathways that facilitate Th2 differentiation and by the development of more intense lesions in mouse strains that fail to downregulate the Th1 response. Genetically prone high-pathology mice have a higher proportion of CD4(+) T cells in lymph nodes and granulomas, in which the Th1 phenotype is driven by interleukin-12; they also develop a dominant repertoire against peptide 234-246 of the major Sm-p40 egg antigen, utilizing a strikingly restricted T-cell receptor structure that involves Valpha11.3beta8. In turn, low-pathology mice exhibit enhanced CD4(+) T-cell apoptosis, which contributes to limit pathology. The definition of distinctive immune profiles associated with polar forms of schistosomiasis opens opportunities for targeted immuno-intervention in individuals suffering from or at risk of severe disease.

Balamuthia mandrillaris, an opportunistic agent of granulomatous amebic encephalitis, infects the brain via the olfactory nerve pathway

Balamuthia mandrillaris is a free-living ameba and an opportunistic agent of lethal granulomatous amebic encephalitis (GAE) in humans and other mammals. Its supposed routes of infection have been largely assumed from what is known about Acanthamoeba spp. and Naegleria fowleri, other free-living amebae and opportunistic encephalitis agents. However, formal proof for any migratory pathway, from GAE patients or from animal models, has been lacking. Here, immunodeficient mice were infected with B. mandrillaris amebae by intranasal instillation, the most likely natural portal of entry. By means of classical and immunohistology, the amebae are shown to adhere to the nasal epithelium, progress along the olfactory nerves, traverse the cribriform plate of the ethmoid bone, and finally infect the brain. A similar invasion pathway has been described for N. fowleri. The data suggest that the olfactory nerve pathway is a likely route for natural infection of the brain by B. mandrillaris amebae.