Continuation of emtricitabine/lamivudine within combination antiretroviral therapy following detection of the M184V/I HIV-1 resistance mutation.

OBJECTIVES: The aim of the study was to investigate whether lamivudine (3TC) or emtricitabine (FTC) use following detection of M184V/I is associated with better virological outcomes. METHODS: We identified people with viruses harbouring the M184V/I mutation in UK multicentre data sets who had treatment change/initiation within 1 year. We analysed outcomes of viral suppression (< 200 HIV-1 RNA copies/mL) and appearance of new major drug resistance mutations (DRMs) using Cox and Poisson models, with stratification by new drug regimen (excluding 3TC/FTC) and Bayesian implementation, and estimated the effect of 3TC/FTC adjusted for individual and viral characteristics. RESULTS: We included 2597 people with the M184V/I resistance mutation, of whom 665 (25.6%) were on 3TC and 458 (17.6%) on FTC. We found a negative adjusted association between 3TC/FTC use and viral suppression [hazard ratio (HR) 0.84; 95% credibility interval (CrI) 0.71-0.98]. On subgroup analysis of individual drugs, there was no evidence of an association with viral suppression for 3TC (n = 184; HR 0.94; 95% CrI 0.73-1.15) or FTC (n = 454; HR 0.99; 95% CrI 0.80-1.19) amongst those on tenofovir-containing regimens, but we estimated a reduced rate of viral suppression for people on 3TC amongst those without tenofovir use (n = 481; HR 0.71; 95% CrI 0.54-0.90). We found no association between 3TC/FTC and detection of any new DRM (overall HR 0.92; 95% CrI 0.64-1.18), but found inconclusive evidence of a lower incidence rate of new DRMs (overall incidence rate ratio 0.69; 95% CrI 0.34-1.11). CONCLUSIONS: We did not find evidence that 3TC or FTC use is associated with an increase in viral suppression, but it may reduce the appearance of additional DRMs in people with M184V/I. 3TC was associated with reduced viral suppression amongst people on regimens without tenofovir.

High-risk behaviours, and their associations with mental health, adherence to antiretroviral therapy and HIV parameters, in HIV-positive men who have sex with men.

OBJECTIVES: To investigate the patterns and frequency of multiple risk behaviours (alcohol, drugs, smoking, higher risk sexual activity) among men who have sex with men (MSM) living with HIV. METHODS: Cross sectional study. RESULTS: 147 out of 819 HIV-positive MSM exhibited a high-risk phenotype (defined as >3 of smoking, excess alcohol, sexually transmitted infection and recent recreational drug use). This phenotype was associated with younger age, depressive symptoms and <90% adherence in multivariable logistic regression. CONCLUSION: In a cohort of MSM, a small, but significant proportion exhibited multiple concurrent risk behaviours.

Highlights of the 2017 European AIDS Clinical Society (EACS) Guidelines for the treatment of adult HIV-positive persons version 9.0.

BACKGROUND: The European AIDS Clinical Society (EACS) Guidelines have since 2005 provided multidisciplinary recommendations for the care of HIV-positive persons in geographically diverse areas. GUIDELINE HIGHLIGHTS: Major revisions have been made in all sections of the 2017 Guidelines: antiretroviral treatment (ART), comorbidities, coinfections and opportunistic diseases. Newly added are also a summary of the main changes made, and direct video links to the EACS online course on HIV Management. Recommendations on the clinical situations in which tenofovir alafenamide may be considered over tenofovir disoproxil fumarate are provided, and recommendations on which antiretrovirals can be used safely during pregnancy have been revised. Renal and bone toxicity and hepatitis C virus (HCV) treatment have been added as potential reasons for ART switches in fully virologically suppressed individuals, and dolutegravir/rilpivirine has been included as a treatment option. In contrast, dolutegravir monotherapy is not recommended. New recommendations on non-alcoholic fatty liver disease, chronic lung disease, solid organ transplantation, and prescribing in elderly are included, and human papilloma virus (HPV) vaccination recommendations have been expanded. All drug-drug interaction tables have been updated and new tables are included. Treatment options for direct-acting antivirals (DAAs) have been updated and include the latest combinations of sofosbuvir/velpatasvir/voxilaprevir and glecaprevir/pibrentasvir. Recommendations on management of DAA failure and acute HCV infection have been expanded. For treatment of tuberculosis (TB), it is underlined that intermittent treatment is contraindicated, and for resistant TB new data suggest that using a three-drug combination may be as effective as a five-drug regimen, and may reduce treatment duration from 18-24 to 6-10 months. CONCLUSIONS: Version 9.0 of the EACS Guidelines provides a holistic approach to HIV care and is translated into the six most commonly spoken languages.

CSF inflammatory markers and neurocognitive function after addition of maraviroc to monotherapy darunavir/ritonavir in stable HIV patients: the CINAMMON study.

CINAMMON is a phase IV, open-label, single-arm, pilot study assessing maraviroc (MVC) in the central nervous system (CNS) when added to darunavir/ritonavir monotherapy (DRV/r) in virologically suppressed HIV-infected subjects. CCR5 tropic participants on DRV/r were recruited. Participants remained on DRV/r for 12 week (w) (control phase). MVC 150 mg qd was added w12-w36 (intervention phase). Lumbar puncture (LP) and neurocognitive function (Cogstate) examinations scheduled at baseline, w12 and w36; MRI before w12, again at w36. Primary endpoint was CSF inflammatory marker changes during intervention phase. Secondary endpoints included changes in NC function and MRI parameters. CSF/plasma DRV/r concentrations measured at w12 and w36, MVC at w36. Nineteen patients recruited, 15 completed (17M, 2F). Dropouts: headache (2), knee problem (could not attend, 1), personal reasons (1). Mean age (range) 45.4 years (27.2-65.1), 13/19 white, 10/19 MSM. No changes in selected CSF markers were seen w12-w36. Overall NC function did not improve w12-w36: total age adjusted z score improved by 0.27 (weighted paired t test; p = 0.11); for executive function only, age adjusted z score improved by 0.54 (p = 0.03). MRI brain parameters unchanged. DRV plasma:CSF concentration ratio unchanged between w12 (132) and w36 (112; p = 0.577, Wilcoxon signed-rank). MVC plasma:CSF concentration ratio was 35 at w36. No changes in neuroinflammatory markers seen. In this small study, addition of 24w MVC 150 mg qd to stable DRV/r monotherapy showed possible improvement in executive function with no global NC effect. Learning effect cannot be excluded. This effect should be further evaluated.

Correction to: CSF inflammatory markers and neurocognitive function after addition of maraviroc to monotherapy darunavir/ritonavir in stable HIV patients: the CINAMMON study.

Due to a production error the bottom portion of Figure 1 was omitted. The corrected figure is given below.

Euroguidelines in Central and Eastern Europe (ECEE) conference and the Warsaw Declaration - a comprehensive meeting report.

OBJECTIVES: The objective of this paper is to summarize the outcomes of the Euroguidelines in Central and Eastern Europe (ECEE) conference held in Warsaw in February 2016. The main aim of this conference was to facilitate a discussion on European AIDS Clinical Society (EACS) guidelines implementation across the region and neighbouring countries and to present the current obstacles in benchmarking HIV care in Europe. METHODS: During a 2-day meeting, there were country-based presentations using a predefined template so as to make the data comparable and focus the discussion. Areas covered were country epidemiology, surveillance, national strategy for treatment and prevention, standards of care, access to care and treatment availability. Each participant filled in a questionnaire investigating HIV guidelines usage per country. RESULTS: In total, 16 Central and Eastern Europe (CEE) and neighbouring countries were represented at the conference: Albania, Armenia, Belarus, Croatia, Czech Republic, Estonia, Georgia, Hungary, Lithuania, Moldova, Poland, Romania, Russia, Serbia, Slovakia and Turkey. EACS guidelines version 7.1 were used in 14 (87%) countries. In 11 (69%) countries, national guidelines were available, of which eight had been recently updated. Half of the countries declared that they use World Health Organization (WHO) and Department of Health and Human Services (DHHS) guidelines, over one-third the European Centre for Disease Prevention and Control (ECDC) HIV testing guidelines and one in five the International Antiviral Society-USA (IAS-USA) Panel guidelines from 2012. CONCLUSIONS: Participants declared their will to promote the widespread use of EACS guidelines for HIV infection in the CEE region and neighbouring countries by signing the Warsaw Declaration. They also emphasized the need to increase publishing of data from national cohorts in that region.

Recent trends and patterns in HIV-1 transmitted drug resistance in the United Kingdom.

OBJECTIVES: Transmission of drug-resistant HIV-1 has decreased in the UK since the early 2000s. This analysis reports recent trends and characteristics of transmitted drug resistance (TDR) in the UK from 2010 to 2013. METHODS: Resistance tests conducted in antiretroviral treatment (ART)-naïve individuals between 2010 and 2013 were analysed for the presence of transmitted drug resistance mutations (TDRMs), defined as any mutations from a modified 2009 World Health Organization surveillance list, or a modified 2013 International Antiviral Society-USA list for integrase tests. Logistic regression was used to examine associations between demographics and the prevalence of TDRMs. RESULTS: TDRMs were observed in 1223 (7.5%) of 16 425 individuals; prevalence declined from 8.1% in 2010 to 6.6% in 2013 (P = 0.02). The prevalence of TDRMs was higher among men who have sex with men (MSM) compared with heterosexual men and women (8.7% versus 6.4%, respectively) with a trend for decreasing TDRMs among MSM (P = 0.008) driven by a reduction in nucleoside reverse transcriptase inhibitor (NRTI)-related mutations. The most frequently detected TDRMs were K103N (2.2%), T215 revertants (1.6%), M41L (0.9%) and L90M (0.7%). Predicted phenotypic resistance to first-line ART was highest to the nonnucleoside reverse transcriptase inhibitors (NNRTIs) rilpivirine and efavirenz (6.2% and 3.4%, respectively) but minimal to NRTIs, including tenofovir, and protease inhibitors (PIs). No major integrase TDRMs were detected among 101 individuals tested while ART-naïve. CONCLUSIONS: We observed a decrease in TDRMs in recent years. However, this was confined to the MSM population and rates remained stable in those with heterosexually acquired HIV infection. Resistance to currently recommended first-line ART, including integrase inhibitors, remained reassuringly low.

Antiretroviral resistance at virological failure in the NEAT 001/ANRS 143 trial: raltegravir plus darunavir/ritonavir or tenofovir/emtricitabine plus darunavir/ritonavir as first-line ART.

OBJECTIVES: To describe the pattern of drug resistance at virological failure in the NEAT001/ANRS143 trial (first-line treatment with ritonavir-boosted darunavir plus either tenofovir/emtricitabine or raltegravir). METHODS: Genotypic testing was performed at baseline for reverse transcriptase (RT) and protease genes and for RT, protease and integrase (IN) genes for patients with a confirmed viral load (VL) >50 copies/mL or any single VL >500 copies/mL during or after week 32. RESULTS: A resistance test was obtained for 110/805 (13.7%) randomized participants qualifying for resistance analysis (61/401 of participants in the raltegravir arm and 49/404 of participants in the tenofovir/emtricitabine arm). No resistance-associated mutation (RAM) was observed in the tenofovir/emtricitabine plus darunavir/ritonavir arm, and all further analyses were limited to the raltegravir plus darunavir arm. In this group, 15/55 (27.3%) participants had viruses with IN RAMs (12 N155H alone, 1 N155H + Q148R, 1 F121Y and 1 Y143C), 2/53 (3.8%) with nucleotide analogue RT inhibitor RAMs (K65R, M41L) and 1/57 (1.8%) with primary protease RAM (L76V). The frequency of IN mutations at failure was significantly associated with baseline VL: 7.1% for a VL of <100,000 copies/mL, 25.0% for a VL of ≥100,000 copies/mL and <500,000 copies/mL and 53.8% for a VL of ≥500,000 copies/mL (PTREND = 0.007). Of note, 4/15 participants with IN RAM had a VL < 200 copies/mL at time of testing. CONCLUSIONS: In the NEAT001/ANRS143 trial, there was no RAM at virological failure in the standard tenofovir/emtricitabine plus darunavir/ritonavir regimen, contrasting with a rate of 29.5% (mostly IN mutations) in the raltegravir plus darunavir/ritonavir NRTI-sparing regimen. The cumulative risk of IN RAM after 96 weeks of follow-up in participants initiating ART with raltegravir plus darunavir/ritonavir was 3.9%.

Host and disease factors are associated with cognitive function in European HIV-infected adults prior to initiation of antiretroviral therapy.

OBJECTIVES: Deficits in cognitive function remain prevalent in HIV-infected individuals. The aim of this European multicentre study was to assess factors associated with cognitive function in antiretroviral therapy (ART)-naïve HIV-infected subjects at the time of enrolment in the NEAT 001/Agence Nationale de Recherche sur le SIDA (ANRS) 143 study. METHODS: Prior to starting ART, seven cognitive tests exploring domains including episodic memory, verbal fluency, executive function and psychomotor speed were administered with scores standardized to z-score using the study population sample mean and standard deviation. The primary measure was overall z-score average (NPZ). We assessed associations between baseline factors and test results using multivariable regression models. RESULTS: Of 283 subjects with baseline cognitive assessments, 90% were male and 12% of black ethnicity. Median (interquartile range) age, years of education, years of known HIV infection, baseline CD4 count and baseline HIV RNA were 39 (31, 47) years, 13 (11, 17) years, 1 (0, 4) years, 344 (279, 410) cells/µL and 4.74 (4.28, 5.14) log10 HIV-1 RNA copies/mL, respectively. Forty per cent were current smokers. Factors significantly associated with poorer overall cognitive performance in multivariable models included older age, shorter duration of education, black ethnicity, lower height, and lower plasma HIV RNA. CONCLUSIONS: In this large, European-wide, ART-naïve population with relatively preserved immunity and early HIV infection, cognitive function scores at the time of ART initiation were associated with demographic and HIV-disease factors.

Essentials from the 2015 European AIDS Clinical Society (EACS) guidelines for the treatment of adult HIV-positive persons.

BACKGROUND: The European AIDS Clinical Society (EACS) guidelines are intended for all clinicians involved in the care of HIV-positive persons, and are available in print, online, and as a free App for download for iPhone and Android. GUIDELINE HIGHLIGHTS: The 2015 version of the EACS guidelines contains major revisions in all sections; antiretroviral treatment (ART), comorbidities, coinfections and opportunistic diseases. Among the key revisions is the recommendation of ART for all HIV-positive persons, irrespectively of CD4 count, based on the Strategic Timing of AntiRetroviral Treatment (START) study results. The recommendations for the preferred and the alternative ART options have also been revised, and a new section on the use of pre-exposure prophylaxis (PrEP) has been added. A number of new antiretroviral drugs/drug combinations have been added to the updated tables on drug-drug interactions, adverse drug effects, dose adjustment for renal/liver insufficiency and for ART administration in persons with swallowing difficulties. The revisions of the coinfection section reflect the major advances in anti-hepatitis C virus (HCV) treatment with direct-acting antivirals with earlier start of treatment in individuals at increased risk of liver disease progression, and a phasing out of interferon-containing treatment regimens. The section on opportunistic diseases has been restructured according to individual pathogens/diseases and a new overview table has been added on CD4 count thresholds for different primary prophylaxes. CONCLUSIONS: The diagnosis and management of HIV infection and related coinfections, opportunistic diseases and comorbidities continue to require a multidisciplinary effort for which the 2015 version of the EACS guidelines provides an easily accessable and updated overview.

Monitoring of kidney function in HIV-positive patients.

HIV-positive patients are at increased risk of developing chronic kidney disease. Although guidelines recommend regular monitoring of renal function in individuals living with HIV, the optimal frequency remains to be defined. In this review, we discuss the renal syndromes that may be identified at an earlier stage via routine assessment of kidney function, and provide guidance in terms of the frequency of monitoring, the most useful tests to perform, and their clinical significance. Specifically, we address whether annual monitoring of kidney function is appropriate for the majority of HIV-positive patients.

The effect of initiation of antiretroviral therapy on monocyte, endothelial and platelet function in HIV-1 infection.

OBJECTIVES: Monocyte activation, endothelial dysfunction and platelet activation all potentially contribute to the increased risk of cardiovascular disease (CVD) reported in those with HIV-1 infection. To date, no study has examined how initiation of antiretroviral therapy (ART) affects markers of all three processes. We aimed to compare markers of monocyte, endothelial and platelet function between untreated HIV-positive subjects and HIV-negative controls and to examine the early effects of ART initiation on these markers. METHODS: We measured monocyte [soluble CD14 (sCD14) and sCD163], endothelial [von Willebrand factor (vWF), intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1)] and platelet [soluble P-selectin (sP-selectin), soluble CD40 ligand (sCD40L) and soluble glycoprotein VI (sGPVI)] biomarkers before and at weeks 4 and 12 post ART initiation in HIV-positive and well-matched HIV-negative controls. RESULTS: We examined 40 subjects, 25 HIV-positive subjects and 15 controls, with a median age of 34 years [interquartile range (IQR) 31, 40 years], of whom 60% were male and 47.5% Caucasian. Pre-ART, all biomarkers (monocyte, endothelial and platelet) were significantly higher in HIV-positive patients versus controls (all P < 0.05) and decreased with ART initiation, except for sCD14, which remained unchanged [median 1680 (IQR 1489, 1946) ng/mL at week 12 versus 1570 (IQR 1287, 2102) ng/mL at week 0; P = 0.7]. Although platelet activation markers reduced to levels comparable to those in controls, endothelial dysfunction markers remained elevated, as did sCD163 [at week 12, median 1005 (IQR 791, 1577) ng/mL in HIV-positive patients versus 621 (IQR 406, 700) ng/mL in controls; P < 0.0001]. CONCLUSIONS: ART initiation resulted in reductions in levels of CVD-associated biomarkers; however, although they improved, markers of endothelial dysfunction and monocyte activation remained elevated. How these persistent abnormalities affect CVD risk in HIV infection remains to be determined.

[Role of Chlamydia trachomatis intraocular infection in the development of proliferative vitreoretinopathy (experimental study)].

OBJECTIVE: To study the influence of C. trachomatis infection on proliferative vitreoretinopathy (PVR) stimulation and development in an experimental model. MATERIAL AND METHODS: Intravitreal C. trachomatis injection was performed in 17 rabbits (right eyes) out of which 8 developed minimal chlamydial damage (1 was further subjected to histopathological examination with pathogen detection in ocular structures and other 7 were included in the study group). The control group consisted of 7 rabbits with no laboratory evidence of chlamydial infection. PVR was induced by 4 peripheral retinal punctures with a 19 G needle. Follow-up methods included ophthalmoscopy, ultrasonography, and PVR grading according to the Fastenberg classification. Histopathological examination, supplemented with pathogen detection by direct immunofluorescence in the study group, was performed at weeks 7 and 20. RESULTS: PVR rate and severity were higher in the study group as compared with the controls (5 out of 7 rabbits, grade 2-4 vs. 2 out of 7 rabbits, grade 0-1, p<0.01). In the study group, histopathological examination performed before and after the induction of PVR revealed a pronounced lymphocyte and macrophage infiltration, characteristic of infectious inflammation. Similarly, extra- and intracellular chlamydial inclusions could be found in the retina and/or zones of proliferation throughout the whole study period. Inflammation signs (including those of proliferation) were reliably less significant in the controls. CONCLUSION: C. trachomatis infection of the posterior segment contributes to PVR development due to associated chronic inflammation.

Pharmacological management of cardiovascular conditions and diabetes in older adults with HIV infection.

This review looks at the evidence for potential and theoretical risks of combining antiretroviral treatment with drugs prescribed for cardiovascular disease and diabetes. These conditions are common in the HIV-infected population as a result of ageing and the increased risk associated with both HIV infection and antiretroviral intake.

Screening for HIV-related neurocognitive impairment in clinical practice: challenges and opportunities.

With increasingly successful management of HIV, focus has shifted away from AIDS-related complications to other chronic co-morbidities. For HIV-related cognitive problems, the true aetiopathogenesis and epidemiology remains unclear. Rather than a systematic review, this paper presents the challenges and the opportunities we faced in establishing our own clinical service. Papers were identified using Pubmed and the terms "screening", "HIV" and "neurocognitive". This article covers the background of HIV-associated neurocognitive disorders (HAND) with a focus on HIV-related neurocognitive impairment (NCI), detailing classification, prevalence, diagnostic categories and diagnostic uncertainties. Screening is discussed, including a comparison of the available screening tools for cognitive deficits in HIV-infected patients and the importance of practice effects. Discussed also are the normal ranges and the lack thereof and potential investigations for those found to have impairments. We conclude by discussing the role of NCI screening in routine clinical care at the current time.

[Role of Chlamydia trachomatis and Chlamydophila pneumoniae in damage of eye posterior segment structures].

AIM: Study the ability of Chlamydia trachomatis and Chlamydophila pneumoniae to damage structures of eye posterior segment, features of development of such infectious process, its morphological and clinical characteristics. MATERIALS AND METHODS: 6 rabbits with confirmed absence of C. trachomatis, C. pneumoniae were used in the study. 3 animals were infected with C. trachomatis culture and 3 animals--with C. pneumoniae culture. Subconjunctival and intravitreal mode of infectious agent introduction were used, as well as instillation of its culture into conjunctival sac. Microbiological diagnostics included microscopy with direct immunofluorescence, culture method and determination of antibody titers. Infectious process was studied by using ophthalmologic methods and histological examination. Observation period was 4 months. RESULTS: In all the animals a development of infectious process at early stages after the infection was confirmed. Conjunctivitis symptoms, inflammatory exudation into vitreous humor, chorioretinal inflammation loci, disorders in transparency of optical media and detachment of retina were clinical manifestations. In 2 animals infected with C. trachomatis severe panuveitis was noted. In 4 animals infectious process assumed subclinical characteristics (infection with both C. trachomatis or C. pneumoniae). In pathomorphologic studies data on the ability of C. trachomatis and C. pneumoniae to cause damage to cells of retina, pigment epithelium and choroid were obtained. CONCLUSION: C. trachomatis and C. pneumoniae may play a significant role in pathology of vitreous humor, retina, pigment epithelium and choroid.

[Dystrophic changes of vitreous in ocular chlamydia infection].

Incidence and character of vitreous changes in ocular chlamydia infection was studied. 312 patients were enrolled into the study (175 males and 137 females) aged from 24 to 52 years old (mean age 38.4 +/- 5.2 years). 165 patients (330 eyes) with laboratory confirmed chlamydia conjunctival infection were included in the experimental group. 147 patients (294 eyes) without chlamydia conjunctival infection were enrolled to the comparison group. Each group was subdivided with regard to the age. Dystrophic changes of vitreous and its posterior detachment are more frequently revealed in eyes with Chlamydia trachomatis infection, besides it happens in a younger age.

[About development of chlamydia multiple organ lesions after primary ocular infection in experiment].

Chlamidia spp. are obligate intracellular pathogens that cause a variety of diseases in humans and animals. Their generalization was proved as hematogenic spreading from the urogenital (C. trachomatis) and the respiratory (C. pneumoniae) systems. The goal was to investigate the possibility of C. trachomatis infection spreading from the primary ocular gate. 6 animals were infected by instillation in the conjunctival sack, subconjunctival and intravitreal injections of C. thachomatis culture. C. trachomatis was detected by direct immunofluorescence method in the retina, retinal pigment epithelium, choroid, brain, the pancreas, the prostate gland and the urethra after primary ocular infection. The results of our study have proved the opportunity of C. trachomatis to cause polyorganic contamination.

Clinical management of tuberculosis and HIV-1 co-infection.

In many parts of the world the commonest serious opportunistic infection that occurs in HIV-1 infected persons is tuberculosis (TB). HIV-1 co-infection modifies the natural history and clinical presentation, and adversely affects the outcome of TB. Severe disseminated disease is well-recognised but it is increasingly appreciated that early disease characterised by very few or no symptoms is also common. Immunodiagnostic methods to ascertain latent TB in HIV-1 infected persons are compromised in sensitivity. Chemoprevention of HIV-1-associated TB is effective, its benefits are restricted to those which have evidence of immune sensitisation and appear short-lived in areas of high TB burden. Although promising advances in the microbiological diagnosis of TB have recently occurred, the diagnosis of HIV-1-associated TB remains difficult because of more frequent presentation as sputum negative or extrapulmonary disease. Management of co-infected patients can be complex because of overlapping drug toxicities and interactions. Nevertheless consensus is developing that antiretroviral therapy should be provided as soon as practicable after starting TB treatment in HIV-1 co-infected persons. This has the consequence of increasing the frequency of immune reconstitution inflammatory syndrome, the pathogenesis and management of which is poorly defined.

[Retinal lesion in experimental chlamydia eye infection].

Until the present time, ophthalmic chlamydiasis has been generally associated with diseases of auxiliary organs of the eye and its anterior segment: conjunctivitis and iridocyclitis. The morphological substrate of eye posterior segment lesion caused by C. trachomatis and C. pneumonia was studied in this investigation. The pathomorphological pattern characteristic of chlamydia-induced rabbit retinal and vitreous body lesions is composed of vitreoretinal lymphocyte-macrophageal infiltrations of varying intensity, posterior hyaloid membrane detachment, peripheral foci or folding of the retina, impaired nuclei of photoreceptors and bipolar neurons, pigment epithelial damage occurring in different concurrences in relation to the species of a causative agent and the clinical picture.