Drug-induced uveitis in aids patients: two case reports

Patients with acquired immunodeficiency syndrome (AIDS) can develop severe uveitis. Although infectious and autoimmune causes must always be considered, drug induced uveitis is also an important etiology. Herein, we present two case reports illustrating the classical presentation of rifabutin and cidofovir induced uveitis. The first case was a 33 year old woman with AIDS treated with anti-protease and anti-tuberculosis drugs (including rifabutin). She presented with a red painful right eye. There was a strong anterior segment inflammation with fibrinous exudates and a dense vitritis. Rifabutin was stopped and topical steroids and mydriatics were given. Intraocular inflammation and symptoms rapidly resolved. The second patient was a 36 year old woman who presented with a painful decrease of vision in her left eye. She was followed for bilateral CMV retinitis in the setting of AIDS and had recently received 2 systemic injections of cidofovir. Anterior segment inflammation with posterior synechiae in both eyes and folds of Descemet membrane in the left eye were noted. Intraocular pressure was 0 mmHg in the left eye and 10 mmHg in the right eye. Fundus examination disclosed CMV retinitis scars in the right eye and choroidal folds in the macula of the left eye. Cidofovir was discontinued and topical steroids and mydriatics started. Progressively the inflammation decreased and the intraocular pressure returned to normal levels. In conclusion, rifabutin and cidofovir are classical examples of drug induced uveitis with distinct characteristic clinical presentation. Recognition of those entities in AIDS patients can avoid useless and potentially invasive interventions in those fragile people.

Calcium channel blocker nilvadipine, but not diltiazem, inhibits ocular inflammation in endotoxin-induced uveitis

PURPOSE

Calcium channel blockers (CCBs), widely used for hypertensive patients, have recently been shown to inhibit atherosclerosis by their antioxidative action. The aim of the present study was to examine whether the CCBs nilvadipine and diltiazem reduce ocular inflammation in endotoxin-induced uveitis (EIU).

METHODS

EIU was induced in male C57/B6 mice with a single intraperitoneal injection of lipopolysaccharide (LPS). The animals received intraperitoneal injections of either nilvadipine, diltiazem, or vehicle for 5 days before the LPS application. Twenty-four hours after EIU induction, adherent leukocytes to the retinal vasculature were counted with a concanavalin A lectin perfusion-labeling technique. The protein concentration in the aqueous humor was measured to assess blood-ocular barrier breakdown. Retinal levels of intercellular adhesion molecule (ICAM)-1 and monocyte chemotactic protein (MCP)-1 were analyzed by enzyme-linked immunosorbent assay. LPS-stimulated generation of superoxide in murine microvascular endothelial cells was examined with a nitroblue tetrazolium assay.

RESULTS

Compared to vehicle treatment, application of nilvadipine, but not diltiazem, led to significant suppression of EIU-associated retinal leukocyte adhesion, together with anterior-chamber protein leakage, retinal expression of ICAM-1 and MCP-1, and LPS-induced superoxide generation in vitro.

CONCLUSIONS

The CCB nilvadipine exercises an inhibitory effect on the pathogenesis of ocular inflammation through the suppression of inflammation-related molecules.

Paradoxical effect of pertussis toxin on the delayed hypersensitivity response to autoantigens in mice

BACKGROUND

Pertussis toxin (PTX), an exotoxin of Bordetella pertussis, enhances the development of experimental autoimmune diseases such as experimental autoimmune uveitis (EAU) and experimental autoimmune encephalomyelitis (EAE) in rodent models. The mechanisms of the promotion of experimental autoimmune diseases by PTX may be based upon PTX-induced disruption of the blood eye/brain barriers facilitating the infiltration of inflammatory cells, the modulation of inflammatory cell migration and the enhancement of the activation of inflammatory cells. We hypothesized that the facilitation of experimental autoimmunity by PTX suggests that its influence on the in vivo immune response to auto-antigen may differ from its influence on non-self antigens.

METHODOLOGY/PRINCIPAL FINDINGS

We have evaluated the effect of PTX on the simultaneous generation of delayed type hypersensitivity (DTH) responses and autoimmune responses to uveitogenic interphotoreceptor retinoid binding protein peptide (IRBP161-180), encephalitogenic myelin oligodendrocyte glycoprotein peptide (MOG35-55) or ovalbumin (OVA). PTX injection of mice immunized to IRBP peptide161-180 led to (i) the development of EAU as shown by histopathology of the retina, (ii) pro-inflammatory cytokine production by splenocytes in response to IRBP peptide161-180, and (iii) symptomatic EAE in mice immunized with encephalitogenic MOG peptide35-55. However, mice that received PTX had a reduced DTH response to IRBP161-180 peptide or MOG peptide35-55 when challenged distal to the site affected by autoreactive T cells. Moreover, footpad challenge with MOG35-55 peptide reduced EAE in mice immunized with MOG peptide. In contrast, the use of PTX when immunizing with OVA protein or an OVA immunogenic peptide did not affect the DTH response to OVA.

CONCLUSIONS/SIGNIFICANCE

The results suggest that that the reduced DTH response in mice receiving PTX may be specific for autoantigens and autoantigen-reactive T cells are diverted away from ectopic sites that received the autoantigen and towards the tissue site of the autoantigen.

[Rifabutin-associated hypopyon uveitis in patient with acquired immunodeficiency syndrome]

BACKGROUND

Rifabutin-associated uveitis has been recognized and established overseas, but there have been no reports of its occurance in Japan. We report a case of rifabutin-induced hypopyon uveitis in a patient with acquired immunodeficiency syndrome (AIDS).

CASE

A 45-year-old Filipino man with AIDS and pulmonary tuberculosis was on highly active antiretroviral therapy (HAART; lopinavir/ritonavir, zidovudine/lamivudine) and anti-tuberculosis therapy (isoniazid, rifabutin). At 11 weeks after starting rifabutin administration, unilateral acute uveitis with hypopyon developed, which progressed to bilateral uveitis by the following day. Funduscopic examination revealed no vitreo-retinal abnormalities. The uveitis resolved after discontinuation of the rifabutin and initiating topical corticosteroids and mydriatic therapy. No recurrence of the uveitis was noted during a 5-month follow-up period.

CONCLUSION

Rifabutin-associated uveitis with hypopyon should be considered as one possible causes of uveitis.

Novel molecular imaging approach for subclinical detection of iritis and evaluation of therapeutic success

There is an urgent need for early diagnosis in medicine, whereupon effective treatments could prevent irreversible tissue damage. Acute anterior chamber inflammation is the most common form of uveitis and a major cause of vision loss. The proximity of the iris vasculature to the light-permeable cornea and its involvement in ocular inflammation make it an ideal target for noninvasive molecular imaging. To accomplish this, carboxylated fluorescent microspheres (MSs) were conjugated with recombinant P-selectin glycoprotein ligand-1 and systemically injected in endotoxin-induced uveitic animals. MS adhesion in the microcirculation of the anterior and posterior chamber was visualized by intravital microscopy and scanning laser ophthalmoscopy. In iritic animals, significantly higher numbers of recombinant P-selectin glycoprotein ligand-1-conjugated MSs adhered to the endothelium (P = 0.03) matching the increase in leukocyte adhesion. Conjugated MSs specifically interacted with firmly adhering leukocytes, allowing quantification of the endogenous immune response. Topical eye drop treatment with dexamethasone (P < 0.01) or cyclosporine A (P < 0.01) significantly lowered MS adhesion in iris vessels. Surprisingly, topical dexamethasone significantly reduced MS interaction in the fundus vessels (P < 0.01), while cyclosporine A did not. In vivo MS accumulation preceded clinical signs of anterior uveitis and leukocyte adhesion in iris vasculature. This work introduces noninvasive subclinical detection of endothelial injury in the iris vasculature, providing a unique opportunity for quantifying vascular injury and immune response in vivo.

Protective effects of bilberry ( Vaccinium myrtillus L.) extract against endotoxin-induced uveitis in mice

Endotoxin-induced uveitis (EIU), a useful animal model of ocular inflammation, is induced by injection of lipopolysacharide (LPS). These experiments showed that the nitric oxide (NO) level significantly increased in the whole eye homogenate of BALB/C mice 24 h after footpad injection of LPS at a dosage of 100 mg/mouse. However, the elevated NO level was significantly reduced by oral administration of bilberry extract (containing 42.04% anthocyanins) at dosages of 50, 100, and 200 mg/kg/day for 5 days before the LPS injection. In addition, bilberry extract decreased malondialdehyde (MDA) level and increased oxygen radical absorbance capacity (ORAC) level, glutathione (GSH) level, vitamin C level, and total superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. Moreover, bilberry extract increased expression of copper/zinc superoxide dismutase (CuZnSOD), manganese superoxide dismutase (MnSOD), and GPx mRNA. Taken together, bilberry extract showed protective effects against EIU, whereas the effects of bilberry extract (100 and 200 mg/kg/day, 5 days) were dose-dependent. In conclusion, these results provide new evidence to elucidate the beneficial effects of bilberry extract on eye health.

[Toll-like receptor 4 expression in macrophages in endotoxin-induced uveitis in Wistar rats]

OBJECTIVE

To investigate the dynamics and distribution of toll-like receptor 4 (TLR4) in uvea-resident tissue macrophages during endotoxin-induced uveitis (EIU) in Wistar rats.

METHODS

Fifty Wistar rats were randomly divided into five groups (n = 10 per group) based on the following time points: before LPS injection (0 h, control group) and 6, 12, 24, and 48 h after LPS injection. All the rats (except the control group) received a footpad injection of 200 microg of vibrio cholera lipopolysaccharide (LPS). The intensity of anterior segment inflammation was evaluated after the LPS injection. Ten rats each were killed before LPS injection and 6, 12, 24, 48 h after injection. The iris-ciliary body complex and choroid from each eye were removed and cut into segments. Immunohistochemical localization of TLR4 and a resident tissue macrophage marker, cluster of differentiation 163 (CD163), was performed on whole mount isolated iris-ciliary body complexes and choroids. TLR4+ and CD163+ cells in the iris were counted, and the cell density (cells/mm(2)) was calculated. For CD163+ cells, the percent of round pleiomorphic cells in positive staining cells was calculated. The distribution patterns and the phenotypes of cells expressing these two proteins were further characterized by double-labeled immunofluorescence studies. Positive cell density and the percent of round-pleiomorphic CD163+ cells were analyzed by one-way ANOVA followed by least significant difference procedure (LSD) tests for multiple comparisons.

RESULTS

The iris-ciliary body complex did not express TLR4 in normal rats. Six h after the LPS injection, a small number of TLR4+ cells were detected in the irides of two rats. The density of TLR4+ cells in the iris was (506.1 +/- 39.5) cells/mm(2) (12 h), (492.3 +/- 54.5) cells/mm(2) (24 h) and (663.8 +/- 150.2) cells/mm(2) (48 h), respectively. The number of TLR4+ cells significantly increased 12, 24 and 48 h after the injection (F = 167.2, P < 0.001, ANOVA). No changes of morphology of TLR4+ cells were detected 12-48 h after the injection. CD163 was expressed in the uvea in all rats. CD163+ round tissue macrophages were present at all time periods (0-48 h). The proportion of these cells was 13% at 0 h and increased to approximately 80% at 12-48 h. These changes occurred mainly in the macrophages located in the stroma bordering the iris endothelial layer. Double-labeling immunofluorescence demonstrated the co-expression of TLR4 and CD163 in round stroma cells with TLR4 protein located at the cell membrane and CD163 protein in the cytoplasm. TLR4+ cells could not be detected in choroid in any of the rats.

CONCLUSIONS

Iris tissue macrophages expressed TLR4 and TLR4+ cells increased in the iris during EIU. It indicates that TLR4 may play an important role in the pathogenesis of acute anterior uveitis.

[Ocular findings in hepatitis C patients treated with interferon]

The pathology of the liver is associated with many disorders including the eye. We described ocular changes following hepatitis C. The most common ophthalmic findings in hepatitis C patients treated with interferon--involve keratoconjunctivitis, scleritis, dry eye syndrome, uveitis, retinopathy, retinal hemorrhages, anterior ischemic optic neuropathy, retinal vascular changes and macular oedema, as well as electroretinogram, visual field and OCT abnormalities.

[Tracking T lymphocytes proliferation with vital dye CFSE in experimental autoimmune uveitis]

OBJECTIVE

To track T lymphocytes proliferation with vital dye CFSE in experimental autoimmune uveitis (EAU).

METHODS

B10RIII mice were immunized with synthetic peptide of interphotoreceptor retinal-binding protein (IRBP161-180) to develop EAU. The proliferation of IRBP-specific T cell subsets was detected by CFSE staining, fluorescent antibody labeling, and flow cytometry.

RESULTS

The IRBP-specific T cells divided after 4 days of stimulation with IRBP161-180, halving the fluorescence intensity. The proliferations of CD4+ and CD8+ T cells were asynchronous, with CD8+ T cells dividing more vigorously and having more drop in percentage of parent cells (P < 0.01).

CONCLUSION

CFSE-Labeling can detect the proliferation of autoreactive T cells and their subsets in EAU effectively.

ORIGINAL ARTICLE, The Immunomodulator Vasoactive Intestinal Peptide (VIP) Does Not Affect Experimental Autoimmune Uveitis (EAU) in B10.RIII Mice

PURPOSE

Vasoactive intestinal peptide (VIP) exhibits immunomodulatory activities both in vivo and in vitro, including efficient inhibition of murine experimental arthritis. In this study, we investigated the effects of VIP treatment on the induction of experimental autoimmune uveoretinitis (EAU).

METHODS

EAU was induced in B10.RIII mice by immunization with interphotoreceptor retinoid-binding protein (IRBP) using routine methods, but without treatment with pertussis toxin (PTX). VIP was injected i.p. at different doses into mice on alternate days. Mice were tested by conventional methods for ocular inflammation, antibody levels, lymphocyte proliferation, and cytokine release by cultured lymphocytes.

RESULTS

Treatment with VIP, at different doses, had essentially no effect on the development of EAU or antibody production in the B10.RIII mice. The treatment did have variable effects on the low interferon-gamma production by lymphocytes of these mice.

CONCLUSION

Unlike its inhibitory effect in the experimental arthritis system, VIP did not modulate the development of EAU in B10.RIII mice.

Age as a Determinant Factor for Endotoxin Induced Uveitis

PURPOSE

To determine if susceptibility to systemic endotoxin-induced uveitis is an age-related phenomenon in the rabbit.

METHODS

Young and adult rabbits were injected intravenously with 2.5 microg/kg of E. coli endotoxin or saline. Thereafter, the number of exudating cells at 2, 6, 12, 24 and 48 hours were determined. The levels of lipopolysaccharide-binding protein, total protein, prostaglandin-E2, nitric oxide and interleukin-6 in aqueous humor were also determined 24 hours after the injections.

RESULTS

A significant increase in the number of exudating cells and the levels of lipopolysaccharide-binding protein, total protein, prostaglandin-E2 and nitric oxide in aqueous humor was observed only in adult rabbits 24 hours after endotoxin injection. No differences were observed in the increased IL-6 levels.

CONCLUSIONS

Life stage seems to be a critical factor in developing an eye-inflammatory response induced by systemic endotoxin. This could be a consequence of a differential specific activation of the ocular immune response.

Effects of Caffeic Acid Phenethyl Ester on Endotoxin-Induced Uveitis in Rats

PURPOSE

Caffeic acid phenethyl ester (CAPE) has antimicrobial, anti-inflammatory, antioxidant, immunomodulatory, and carcinostatic properties. In this study, the efficacy of CAPE in endotoxin-induced uveitis (EIU) in rats is investigated.

METHODS

EIU was induced by a footpad injection of lipopolysaccharide (LPS). In the treatment group, 10 micromol/kg CAPE was injected intraperitoneally immediately after LPS injection. At 24 hr after LPS injection, the number of infiltrating cells, protein concentration, and levels of myeloperoxidase (MPO) in aqueous humor; malondialdehyde (MDA), MPO, and total antioxidant levels in serum were determined. Eyes were enucleated for histopathologic evaluation, and, counting inflammatory cells in iris-ciliary body (ICB), the efficacy of treatment was determined.

RESULTS

CAPE significantly suppressed LPS-induced increase in the number of inflammatory cells (p = 0.0001), protein concentration (p = 0.0001), and MPO levels (p = 0.0001) in aqueous humor as well as MDA (p = 0.001) and MPO (p = 0.0001) levels in serum. Histopathologic evaluation of ICB showed significant reduction in the inflammatory cell counts in the treatment group (p = 0.0001).

CONCLUSIONS

CAPE was found efficient in suppressing inflammation and ocular tissue damage induced by LPS in rats.

[Can tumor necrosis factor inhibitors induce sclero-uveitis?]

We report three cases of female patients who presented a first episode of unilateral scleritis or acute anterior uveitis while they were treated for 12-16 months by TNF inhibitor: etanercept (Enbrel((R))) 25mg twice weekly for rheumatologic diseases (rheumatoid arthritis or ankylosing spondylitis). Ocular inflammation was resistant to the usual treatment. Some cases of scleritis and uveitis are known to be drug-induced. TNF inhibitors seem to be part of them. Ocular inflammation is usually the first episode. It appears generally in the first year of the treatment by TNF inhibitors and resists to usual treatment. The general disease is usually well stabilized. In our cases, inflammation decreased only when the etanercept was discontinued.

Piroxicam nanoparticles for ocular delivery: Physicochemical characterization and implementation in endotoxin-induced uveitis

To investigate the anti-inflammatory impacts of piroxicam nanosuspension, in the current investigation, piroxicam:Eudragit RS100 nanoformulations were used to control inflammatory symptoms in the rabbits with endotoxin-induced uveitis (EIU). The nanoparticles of piroxicam:Eudragit RS100 was formulated using the solvent evaporation/extraction technique. The morphological and physicochemical characteristics of nanoparticles were studied using particle size analysis, X-ray crystallography, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Drug release profiles were examined by fitting the data to the most common kinetic models. Selected nanosuspensions were used to assess the anti-inflammatory impacts of piroxicam nanoparticles in the rabbits with EIU. The major symptoms of EIU (i.e. inflammation and leukocytes numbers in the aqueous humor) were examined. All the prepared piroxicam formulations using Eudragit RS100 resulted in a nano-range size particles and displayed spherical smooth morphology with positively charged surface, however, the formulated particles of drug alone using same methodology failed to manifest such characteristics. The Eudragit RS100 containing nanoparticles displayed lower crystallinity than piroxicam with no chemical interactions between the drug and polymer molecules. Kinetically, the release profiles of piroxicam from nanoparticles appeared to fit best with the Weibull model and diffusion was the superior phenomenon. The in vivo examinations revealed that the inflammation can be inhibited by the drug:polymer nanosuspension more significantly than the microsuspension of drug alone in the rabbits with EIU. Upon these findings, we propose that the piroxicam:Eudragit RS100 nanosuspensions may be considered as an improved ocular delivery system for locally inhibition of inflammation.

[Intravitreal injection. Monitoring to avoid postoperative complications]

Intravitreal injection is generally regarded as safe. Many of the potential complications caused by this procedure are extremely rare and can be avoided by careful inspection beforehand and proper performance of the injection. In rare cases, however, the administered drugs may cause various pharmacological side effects. This article summarizes the safety profiles of Macugen and Lucentis from the drug approval studies and describes initial findings on possible or observed side effects after intravitreal administration of Avastin. In addition, important points to observe in order to avoid intra- and postoperative complications are provided.

Sarcoidosis presenting with granulomatous uveitis induced by pegylated interferon and ribavirin therapy for Hepatitis C

Sarcoidosis is a systemic granulomatous disease that is triggered by an autoimmune process, and is now a well recognized but uncommon complication of antiviral therapy for Hepatitis C virus (HCV) infection, likely related to its immunomodulatory effects. The clinical presentation of HCV related sarcoidosis is as varied as systemic sarcoidosis, but ocular presentation alone has not been reported previously. We present a 23 year-old female who developed visual disturbances due to ocular sarcoidosis during the course of antiviral therapy for chronic HCV infection. Our case presentation is then followed by a review of the literature on the topic. We aim to stress the importance of screening for eye problems in following HCV patients undergoing antiviral therapy, and raise clinicians' awareness of sarcoidosis as a possible cause for eye problems even in the absence of respiratory complaints.

Characterizing extravascular neutrophil migration in vivo in the iris

Extravascular neutrophil migration is poorly characterized in vivo. To test the hypothesis that this migration is a non-random process, we used videomicroscopy to monitor neutrophils in irises of living mice with endotoxin-induced uveitis (EIU). Paths of individual cells were analyzed. Nearly all of these cells were moving in divergent directions, and mean displacement plots indicated that the predominant movement was random. The paths of some cells were fit to bivariate autoregressive integrated moving average models that revealed at least two modes of movement: random search and linear trend. Cell speed was significantly reduced by the actin inhibitor, cytochalasin D. The pattern of migration for neutrophils is in marked contrast to what we previously described for antigen-presenting cells in the iris, but somewhat resembles recent descriptions for T cells within a lymph node. Characterization of extravascular migration of neutrophils has important implications for understanding infection and immunity.

Altered chemokine profile associated with exacerbated autoimmune pathology under conditions of genetic interferon-gamma deficiency

PURPOSE

A prior study showed that mice deficient in IFN-gamma (GKO) are more susceptible to experimental autoimmune uveitis (EAU) than are wild-type (WT) mice. Histopathology of uveitic eyes revealed that the ocular infiltrate in GKO mice was dominated by neutrophils and eosinophils rather than by mononuclear cells, as in WT mice. The present study was conducted to explore the differential expression of chemokine(s) likely to account for the distinct inflammatory cell composition in uveitic eyes of WT and GKO mice.

METHODS

Mice were immunized to induce EAU. Lymph nodes draining the site of the immunization and the eyes were collected at different time points for chemokine analysis. Microarray, real-time PCR and protein analyses were performed to examine the expression of chemokines in WT and GKO mice.

RESULTS

Many chemokines were differentially upregulated in GKO versus WT mice. Expression of the Th1-associated chemokines CXCL10, CXCL9, CCL5, and CXCL11 was elevated in WT mice, whereas the Th2-associated chemokines CCL11, CCL17, and CCL1 and the Th17-associated chemokines CCL22 and CXCL2 were elevated in the GKO mice. Depletion of granulocytes abrogated EAU in both WT and GKO mice.

CONCLUSIONS

These results suggest that Th1-associated chemokines play a critical role in the attraction of mononuclear cells to the eyes in the presence of IFN-gamma, while in the absence of this cytokine, Th2- and Th17-related chemokines may be the key elements for influx of granulocytes.

Aldose reductase inhibition prevents endotoxin-induced uveitis in rats

PURPOSE

The purpose of the present study was to elucidate the role of the polyol pathway enzyme aldose reductase (AR) in the mediation of ocular inflammation in a rat model of endotoxin-induced uveitis (EIU).

METHODS

EIU was induced by a subcutaneous injection of 200 microg lipopolysaccharide (LPS) in male Lewis rats treated with the AR inhibitor, zopolrestat (25 mg/kg body weight, intraperitoneally) or its carrier. The rats were killed 24 hours after LPS injection, the eyes were enucleated immediately, and aqueous humor (AqH) was collected. The number of infiltrating cells, protein concentration, and levels of nitric oxide (NO), tumor necrosis factor (TNF)-alpha, and prostaglandin E(2) (PGE(2)) in the AqH were determined. Immunohistochemical analysis was performed in paraformaldehyde-fixed eye sections by staining with antibodies against iNOS, COX-2, TNF-alpha, NF-kappaB, and AR. The levels of reactive oxygen species (ROS) in rat eye sections were determined by dihydroethidium (hydroethidine) fluorescence staining.

RESULTS

In the EIU rat eye AqH, both the number of infiltrating cells and protein concentrations of the inflammatory markers, TNF-alpha, NO, and PGE(2) were significantly higher than in the control rats, and inhibition of AR by zopolrestat suppressed the LPS-induced increases. The LPS-induced increased expression of AR, TNF-alpha, iNOS, and COX-2 proteins in the ciliary body, corneal epithelium, and retinal wall was also significantly inhibited by zopolrestat. Furthermore, AR inhibition prevented the LPS-induced increased levels of ROS and activation of NF-kappaB in the ciliary body, corneal epithelium, and retinal wall of the rat eye. AR inhibition also prevented the LPS-induced activation of NF-kappaB and expression of COX-2 and iNOS in the human monocyte cell line U-937.

CONCLUSIONS

The results indicate that AR inhibition suppresses the inflammation in EIU by blocking the expression and release of inflammatory markers in ocular tissues, along with the attenuation of NF-kappaB activation. This finding suggests that AR inhibition could be a novel therapeutic target for the treatment of uveitis and associated ocular inflammation.

[Recurrent new-onset uveitis in a patient with rheumatoid arthritis during anti-TNFalpha treatment]

Inflammation involving the uveal tract of the eye, termed uveitis, is frequently associated with various rheumatic disease, including seronegative spondylarthropathies, juvenile rheumatoid arthritis, Crohn's disease and Behçet's disease. Scleritis and keratitis may be associated with rheumatoid arthritis and systemic vasculitides such as Wegener's granulomatosis. Immune-mediated uveitis can have a chronic relapsing course and produce numerous possible complications, many of which can result in permanent vision loss. Treatment typically includes topical or systemic corticosteroids with cycloplegic-mydriatic drugs and/or noncorticosteroid immunosuppressants, but often there is an insufficient clinical effectiveness. Anti-TNFalpha therapy is promising in the treatment of sight threatening uveitis, particularly in patients with Behçet's disease. However, there have been also reports of new-onset uveitis during treatment of joint disease with TNFalpha inhibitors. We describe a case of new-onset uveitis in a patient with rheumatoid arthritis during therapy with etanercept at first and infliximab at last. Although we cannot exclude uveitis as linked to rheumatoid arthritis, it is unlike that the uveitis arises when the joint disease is well controlled. The hypothetical paradoxical effect of anti-TNF is here discussed.

Rifabutin for treating pulmonary tuberculosis

BACKGROUND

Rifamycins are an essential component of modern short-course regimens for treating tuberculosis. Rifabutin has favourable pharmacokinetic and pharmacodynamic properties and is less prone to drug-drug interactions than rifampicin. It could contribute to shortening of therapy or simplify treatment in HIV-positive people who also need antiretroviral drugs.

OBJECTIVES

To compare combination drug regimens containing rifabutin with those containing rifampicin for treating pulmonary tuberculosis

SEARCH STRATEGY

We searched Cochrane Infectious Diseases Group Specialized Register (January 2007), CENTRAL (The Cochrane Library 2006, Issue 4), MEDLINE (1966 to January 2007), EMBASE (1974 to January 2007), and LILACS (1982 to January 2007). We also searched the Indian Journal of Tuberculosis (1983 to 2006), conference abstracts, reference lists, and unpublished data on file at Pfizer Inc.

SELECTION CRITERIA

Randomized and quasi-randomized trials including participants with sputum smear and/or culture-confirmed tuberculosis that compared a rifabutin-containing with an otherwise identical rifampicin-containing regimen.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility and methodological quality, and extracted data. Dichotomous data were analysed and combined using relative risks (RR) with 95% confidence intervals (CI) using a fixed-effect model. Subgroup analyses were carried out according to rifabutin dose.

MAIN RESULTS

Five trials with a total of 924 participants met the inclusion criteria; 5% of participants were HIV positive. Only one small trial was methodologically adequate. The two largest trials (818 participants) had unclear allocation concealment and included < 90% of randomized participants in the analysis. There was no statistically significant difference in between the regimens for cure (RR 1.00, 95% CI 0.96 to 1.04; 553 participants, 2 trials) or relapse (RR 1.23, 95% CI 0.45 to 3.35; 448 participants, 2 trials). The number of adverse events was not significantly different (RR 1.42, 95% CI 0.88 to 2.31; 714 participants, 3 trials), though the RR increased with rifabutin dose: 150 mg (RR 0.98, 95% CI 0.45 to 2.12; 264 participants, 2 trials); and 300 mg (RR 1.78, 95% CI 0.94 to 3.34; 450 participants, 2 trials). However, lack of dose adjustment by weight in the relevant trials complicates interpretation of this relationship.

AUTHORS' CONCLUSIONS

The replacement of rifampicin by rifabutin for first-line treatment of tuberculosis is not supported by the current evidence. HIV-positive people with tuberculosis, the group most likely to benefit from the rifabutin use, are under-represented in trials to date, and further trials in this group would be useful.

Inhibition of Endotoxin-Induced Uveitis by Methylprednisolone Acetate Nanosuspension in Rabbits

PURPOSE

In this study, nanoformulations of methylprednisolone acetate (MPA) were formulated by using a copolymer of poly(ethylacrylate, methyl-methacrylate and chlorotrimethyl-ammonioethyl methacrylate) to study their impacts on the inhibition of inflammatory symptoms in rabbits with endotoxin-induced uveitis (EIU).

METHODS

A modified quasiemulsion solvent diffusion technique was used for the preparation of the nanoparticles. The drug-release profiles and physicochemical characteristics of the nanoformulations were studied by means of X-ray crystallography, differential scanning calorimetry, and Fourier transform infrared spectroscopy. Particle-size analysis yielded mean diameters of approximately 380, 460, and 580 (nm) for copolymer nanoparticles at the ratios of 1:2.5, 1:5, and 1:10, respectively. Major clinical symptoms of EIU (e.g., morphologic changes, leukocytes numbers, and protein levels within the aqueous humor) were examined.

RESULTS

Upon the physicochemical characterizations, no crystal changes or chemical interactions were observed for the copolymer nanoparticles. The 1:2.5 ratio of drug polymer resulted in the most controlled release of MPA. The in vivo examinations revealed that the endotoxin-induced inflammation can be inhibited by the copolymer nanosuspension more significantly than by the microsuspension of MPA itself in the rabbits with EIU.

CONCLUSIONS

Based on our findings, we suggest that the copolymer nanosuspension may favor the localized, controlled ocular delivery of MPA for the prevention of inflammatory symptoms in ocular diseases.