Cumulative incidence and risk of infection in patients with rheumatoid arthritis treated with janus kinase inhibitors: A systematic review and meta-analysis.

Patients with rheumatoid arthritis (RA) who receive immunosuppressive medications have a heightened risk of infection. The goal of our study was to calculate the pooled cumulative incidence and risk of infection in patients with RA treated with Janus kinase inhibitors (JAKi). The PubMed and EMBASE databases were queried for randomized controlled trials comparing patients with RA treated with JAKi (upadacitinib, baricitinib, tofacitinib, peficitinib, or filgotinib), defined as the treatment group, compared with control subjects, defined as participants receiving placebo or treatment regimen that was similar to that of participants in the treatment group, with the exception of JAKi. The primary study endpoint was the relative risk (RR) of any-grade and severe infection. The secondary endpoints were RR and cumulative incidence of opportunistic infections, herpes zoster, and pneumonia. The Stata v17 software was used for all data analysis. Results showed that treatment with baricitinib was associated with an increased risk of any-grade (RR 1.34; 95% CI: 1.19-1.52) and opportunistic (RR 2.69; 95% CI: 1.22-5.94) infection, whereas treatment with filgotinib (RR 1.21; 95% CI: 1.05-1.39), peficitinib (RR 1.40; 95% CI: 1.05-1.86) and upadacitinib (RR 1.30; 95% CI: 1.09-1.56) was associated with increased risk of any-grade infection only. Analysis based on type of infection showed a pooled cumulative incidence of 32.44% for any-grade infections, 2.02% for severe infections, 1.74% for opportunistic infections, 1.56% for herpes zoster, and 0.49% for pneumonia in patients treated with any JAKi during the follow-up period. Treatment with specific JAKi in patients with RA is associated with an increased risk of any-grade and opportunistic infections but not severe infection. Close clinical monitoring of patients with RA treated with JAKi is required to establish the long-term infection risk profile of these agents.

Navigating commensal dysbiosis: Gastrointestinal host-pathogen interplay orchestrating opportunistic infections.

The gut commensals, which are usually symbiotic or non-harmful bacteria that live in the gastrointestinal tract, have a positive impact on the health of the host. This review, however, specifically discuss distinct conditions where commensals aid in the development of pathogenic opportunistic infections. We discuss that the categorization of gut bacteria as either pathogens or non-pathogens depends on certain circumstances, which are significantly affected by the tissue microenvironment and the dynamic host-microbe interaction. Under favorable circumstances, commensals have the ability to transform into opportunistic pathobionts by undergoing overgrowth. These conditions include changes in the host's physiology, simultaneous infection with other pathogens, effective utilization of nutrients, interactions between different species of bacteria, the formation of protective biofilms, genetic mutations that enhance pathogenicity, acquisition of genes associated with virulence, and the ability to avoid the host's immune response. These processes allow commensals to both initiate infections themselves and aid other pathogens in populating the host. This review highlights the need of having a detailed and sophisticated knowledge of the two-sided nature of gut commensals. Although commensals mostly promote health, they may also become harmful in certain changes in the environment or the body's functioning. This highlights the need of acknowledging the intricate equilibrium in interactions between hosts and microbes, which is crucial for preserving intestinal homeostasis and averting diseases. Finally, we also emphasize the further need of research to better understand and anticipate the behavior of gut commensals in different situations, since they play a crucial and varied role in human health and disease.

Rhinocerebral mucormycosis and Trichosporon asahii fungemia in a pediatric patient with acute lymphoblastic leukemia: a rare coinfection.

Mucormycosis is a rare life-threatening opportunistic infection, with rhinocerebral mucormycosis (ROCM) being the most common presentation. Trichosporon asahii is an emerging pathogen that often causes fatal infections in patients with underlying hematologic malignancies due to its high drug resistance. We report a rare case of concomitant rhinocerebral mucormycosis and T. asahii fungemia secondary to Pseudomonas aeruginosa sepsis in a patient with neutropenia and acute lymphoblastic leukemia. A boy aged one year and two months was diagnosed with B-cell acute lymphoblastic leukemia on January 10 and underwent three courses of regular chemotherapy. He experienced neutropenia for 154 days and was hospitalized for vomiting, diarrhea and fever for 3 days. The day after hospitalization, Pseudomonas aeruginosa was isolated by blood culture and ceftazidime/avibactam was administered. Extracorporeal Membrane Oxygenation (ECMO) was used to provide continuous extracorporeal respiration and circulation for the patient. On day 8, the patient developed T. asahii fungemia. On day 10, he presented with necrotizing skin caused by Rhizopus delemar. He was treated with liposomal amphotericin B for Rhizopus delemar and voriconazole for T. asahii infection. Unfortunately, his health deteriorated and he died on day 11 due to the rapid progression of the infection and multiple organ failure. The management and treatment of such a complex infection requires a multidisciplinary approach and close monitoring of the patient's condition. Therefore, it is imperative to continue to research and report rare cases such as this to further understand the complexities of mucormycosis and trichosporidiosis coinfection and improve patient outcomes.

Experience of dermatologic biologic therapy use and associated opportunistic infection management in Australia's tropical north.

BACKGROUND/OBJECTIVES: Royal Darwin Hospital (RDH) is the sole public dermatology service in the Northern Territory (NT). Prescription of biologic therapies (BT) in the NT is uniquely challenging, with remote populations carrying a high tropical disease burden. The aim of this audit is to examine the demographics and outcomes of patients on BT for dermatologic conditions. METHODS: Retrospective case note review of patients receiving BT through the RDH Dermatology department between August 2021 and October 2023. Data analysed were demographics, location, dermatological diagnosis and serology status. RESULTS: In this audit, 115 patients were included. Age range of 13-91 years, mean of 51.1 years (±14.7), 52 (45.2%) patients were female and 8 (7.8%) identified as First Nations Australian. A large geographical area was serviced, with a primary address between 1 and 1496 km from RDH. Eighteen patients (15.7%) have discontinued BT completely. There was a statistically significant relationship between cessation of BT and increased distance of primary residence from RDH (p < 0.0007). Eighteen patients (15.7%) required management of infections identified in opportunistic infection screening. These infections were strongyloidiasis, tuberculosis, melioidosis and hepatitis B. CONCLUSIONS: There is significant anxiety surrounding BT and tropical infections, including in returning travellers in southern Australian states. There has been particular interest in strongyloidiasis infection, as dupilumab acts on the Th2 immunity mechanism critical to parasitic infection response. This audit exhibits the unique experience of dermatological care in a tropical setting, demonstrating how BT can be used safely and how, when identified, these tropical infections can be successfully managed.

The pathogenicity and virulence of the opportunistic pathogen Staphylococcus epidermidis.

The pervasive presence of Staphylococcus epidermidis and other coagulase-negative staphylococci on the skin and mucous membranes has long underpinned a casual disregard for the infection risk that these organisms pose to vulnerable patients in healthcare settings. Prior to the recognition of biofilm as an important virulence determinant in S. epidermidis, isolation of this microorganism in diagnostic specimens was often overlooked as clinically insignificant with potential delays in diagnosis and onset of appropriate treatment, contributing to the establishment of chronic infection and increased morbidity or mortality. While impressive progress has been made in our understanding of biofilm mechanisms in this important opportunistic pathogen, research into other virulence determinants has lagged S. aureus. In this review, the broader virulence potential of S. epidermidis including biofilm, toxins, proteases, immune evasion strategies and antibiotic resistance mechanisms is surveyed, together with current and future approaches for improved therapeutic interventions.

Hospitalizations for opportunistic infections following transplantation and associated risk factors: A national cohort study of Medicare beneficiaries.

BACKGROUND: Opportunistic infections (OIs) are a significant cause of morbidity and mortality after organ transplantation, though data in the liver transplant (LT) population are limited. METHODS: We performed a retrospective cohort study of LT recipients between January 1, 2007 and Deceber 31, 2016 using Medicare claims data linked to the Organ Procurement and Transplantation Network database. Multivariable Cox regression models evaluated factors independently associated with hospitalizations for early (≤1 year post transplant) and late (>1 year) OIs, with a particular focus on immunosuppression. RESULTS: There were 11 320 LT recipients included in the study, of which 13.2% had at least one OI hospitalization during follow-up. Of the 2638 OI hospitalizations, 61.9% were early post-LT. Cytomegalovirus was the most common OI (45.4% overall), although relative frequency decreased after the first year (25.3%). Neither induction or maintenance immunosuppression were associated with early OI hospitalization (all p > .05). The highest risk of early OI was seen with primary sclerosing cholangitis (aHR 1.74; p = .003 overall). Steroid-based and mechanistic target of rapamycin inhibitor-based immunosuppression at 1 year post LT were independently associated with increased late OI (p < .001 overall). CONCLUSION: This study found OI hospitalizations to be relatively common among LT recipients and frequently occur later than previously reported. Immunosuppression regimen may be an important modifiable risk factor for late OIs.

Mucormycosis in Liver Allograft Following Transplant for Secondary Biliary Cirrhosis.

Mucormycosis, a group of opportunistic mycoses caused by Mucorales, present a significant threat to immunocompromised patients. In this report, we present the case of a 57-year-old male patient who underwent liver transplant for secondary biliary cirrhosis following inadvertent bile duct injury. Despite initial satisfactory postoperative evolution, the patient developed fever, and imaging revealed a suspicious lesion. Preliminary culture growth suggested a filamentous fungus, leading to initiation of liposomal amphotericin B. However, the lesion progressed, and a surgical debridement was necessary. During surgery, involvement of the liver dome and diaphragm was observed, and a nonanatomical hepatectomy was performed. Despite efforts, the patient's condition deteriorated, ultimately resulting in multiple organ failure and mortality. This case emphasizes the challenging nature of mucormycosis in livertransplant recipients.

Clinicopathologic Spectrum and Outcomes of Infections Diagnosed on Graft Biopsies and Nephrectomy in Live Renal Allograft Recipients: An Institutional Experience.

OBJECTIVES: Modern immunosuppressive regimens have reduced rejection episodes in renal allograft recipients but have increased the risk of opportunistic infections. Infections are considered to be the second leading cause of death after cardiovascular complications in renal allograft recipients. Data on opportunistic infections affecting the allograft itself are scarce. The present study describes the spectrum of renal opportunistic infections and their outcomes diagnosed on renal allograft biopsies and nephrectomy specimens. MATERIALS AND METHODS: Our retrospective observational study was conducted from December 2011 to December 2021. We analyzed infectious episodes diagnosed on renal allograft biopsies or graft nephrectomy specimens. We obtained clinical, epidemiological, and laboratory details for analyses from hospital records. RESULTS: BK virus nephropathy was the most common opportunistic infection affecting the allograft, accounting for 47% of cases, followed by bacterial graft pyelonephritis (25%). Mucormycosis was the most common fungal infection. The diagnosis of infection from day of transplant ranged from 14 days to 39 months. Follow-up periods ranged from 1 to 10 years. Mortality was highest among patients with opportunistic fungal infection (62%), followed by viral infections, and graft failure rate was highest in patients with graft pyelonephritis (50%). Among patients with BK polyomavirus nephropathy, 45% had stable graft function compared with just 33% of patients with bacterial graft pyelonephritis. CONCLUSIONS: BK polyoma virus infection was the most common infection affecting the renal allograft in our study. Although fungal infections caused the highest mortality among our patients, bacterial graft pyelonephritis was responsible for maximum graft failure. Correctly identifying infections on histology is important so that graft and patient life can be prolonged.

A Novel Homozygous RHOH Variant Associated with T Cell Dysfunction and Recurrent Opportunistic Infections.

RHOH, an atypical small GTPase predominantly expressed in hematopoietic cells, plays a vital role in immune function. A deficiency in RHOH has been linked to epidermodysplasia verruciformis, lung disease, Burkitt lymphoma and T cell defects. Here, we report a novel germline homozygous RHOH c.245G > A (p.Cys82Tyr) variant in a 21-year-old male suffering from recurrent, invasive, opportunistic infections affecting the lungs, eyes, and brain. His sister also succumbed to a lung infection during early adulthood. The patient exhibited a persistent decrease in CD4+ T, B, and NK cell counts, and hypoimmunoglobulinemia. The patient's T cell showed impaired activation upon in vitro TCR stimulation. In Jurkat T cells transduced with RHOHC82Y, a similar reduction in activation marker CD69 up-regulation was observed. Furthermore, the C82Y variant showed reduced RHOH protein expression and impaired interaction with the TCR signaling molecule ZAP70. Together, these data suggest that the newly identified autosomal-recessive RHOH variant is associated with T cell dysfunction and recurrent opportunistic infections, functioning as a hypomorph by disrupting ZAP70-mediated TCR signaling.

Severe infections in systemic necrotizing vasculitis.

Infections in patients with systemic vasculitis represent one of the main causes of mortality. Corticosteroid use, immunosuppressive therapy, age, associated organic involvement and dialysis dependence are risk factors of infection. OBJECTIVES: To determine the prevalence of severe infection and associated factors in patients diagnosed with ANCA-associated vasculitis (AAV) and Polyarteritis Nodosa (PAN). METHODS: retrospective study was conduced in a single rheumatology center (2000-2018). We included patients diagnosed with AAV (Granulomatosis with Polyangiitis (GPA), Eosinophilic Granulomatosis with Polyangiitis (EGPA) and Microscopic Polyangiitis (PAM) and Polyarteritis nodosa (PAN). Serious infectious events requiring hospitalisation or prolonged antibiotic/antiviral treatment, recurrent infection of Herpes Zoster Virus or opportunistic infections were evaluated. Sites of infection, isolated microorganisms and mortality related were analyzed. RESULTS: 105 patients were analyzed, follow-up time median 18 m, 58.7% were women and median age was 52 years. Types of vasculitis: 41.9% PAM, 16.2% EPGA, 40% GPA, 1.9% PAN. Constitutional, pulmonary, renal and otorhinolaryngology manifestations were the most frequent. PREVALENCE OF INFECTION: 34.2%, with a median of 3 months from diagnosis of vasculitis to the infectious event. Low respiratory tract (42.8%), sepsis (31.4%), and urinary tract (14.3%) were the most common sites of infections. Bacterial aetiology was the most prevalent (67.7%). Mortality at the first event was 14.3% and a 72.2% of patients were in the induction phase of treatment. Infectious events were significantly associated with age > 65 years (p = 0.030), presence of lung (p = 0.016) and renal involvement (p = 0.001), BVASv3 > 15, mortality (p = 0.0002). CONCLUSIONS: The prevalence of infection was 34.2%. Lower airway infections, septicemia and urinary tract infections were the most prevalent. Infections were associated with renal and pulmonary involvement, age older than 65 years and score BVAS > 15. Severe infections were associated with mortality, especially in elderly patients.

Advances in pharmacotherapies for cytomegalovirus infection: what is the current state of play?

INTRODUCTION: Cytomegalovirus (CMV) remains a serious opportunistic infection in hematopoietic cell transplant (HCT) and solid-organ transplant (SOT) recipients. Traditional anti-CMV drugs are limited by toxicities and the development of resistance. Letermovir and maribavir are newly approved antivirals for the prevention and treatment of CMV. AREAS COVERED: Prior reviews have discussed use of letermovir for prevention of CMV after HCT and maribavir for resistant or refractory (R/R) CMV post HCT or SOT. Subsequent data have expanded their use including letermovir for primary CMV prophylaxis in high-risk renal transplant recipients and new recommendations for extending prophylaxis through day + 200 in certain HCT patients. Data on the use of maribavir for first asymptomatic CMV infection post-HCT has also been published. This review compares the pharmacology of anti-CMV agents and discusses the updated literature of these new drugs in the prevention and treatment of CMV. EXPERT OPINION: Letermovir and maribavir are much needed tools that spare toxicities of ganciclovir, foscarnet, and cidofovir. High cost is a challenge preventing their integration into clinical practice in resource-limited countries. Transplant centers need to exercise restraint in overuse to avoid resistance, particularly in the setting of high viral loads.

Dietary restriction rescues 5-fluorouracil-induced lethal intestinal toxicity in old mice by blocking translocation of opportunistic pathogens.

Chemotherapy remains a major treatment for malignant tumors, yet the application of standard dose intensity chemotherapy is limited due to the side effects of cytotoxic drugs, especially in old populations. The underlying mechanisms of cytotoxicity and strategies to increase the safety and tolerance of chemotherapy remain to be explored. Using 5-fluorouracil (5-FU), a cornerstone chemotherapeutic drug, we demonstrate that the main cause of death in ad libitum (AL) fed mice after 5-FU chemotherapy was infection caused by translocation of intestinal opportunistic pathogens. We show that these opportunistic pathogens greatly increase in the intestine after chemotherapy, which was closely related to loss of intestinal lysozyme. Of note, two weeks of dietary restriction (DR) prior to chemotherapy significantly protected the loss of lysozyme and increased the content of the beneficial Lactobacillus genera, resulting in a substantial inhibition of intestinal opportunistic pathogens and their translocation. The rescue effect of DR could be mimicked by Lysozyme or Lactobacillus gavage. Our study provides the first evidence that DR achieved a comprehensive protection of the intestinal physical, biological and chemical barriers, which significantly improved the overall survival of 5-FU-treated mice. Importantly, the above findings were more prominent in old mice. Furthermore, we show that patients over 65 years old have enriched opportunistic pathogens in their gut microbiota, especially after 5-FU based chemotherapy. Our study reveals important mechanisms for the poor chemotherapy tolerance of the elderly population, which can be significantly improved by short-term DR. This study generates new insights into methods for improving the chemotherapeutic prognosis by increasing the chemotherapy tolerance and safety of patients with malignant tumors.

Implementation of a rapid diagnostic assay package for cryptococcosis, histoplasmosis and tuberculosis in people living with HIV in Paraguay.

BACKGROUND: Opportunistic infections (OIs) are common causes of mortality among people living with HIV (PLHIV). We determined prevalence and 30-day mortality due to histoplasmosis, cryptococcosis, and TB in PLHIV with advanced HIV disease (AHD). METHODS: PLHIV 18 years and older, with a CD4 + T-cell count of less than 350 cells/mm3 newly diagnosed with HIV infection or re-engaged in care after being without ART for more than 90 days (Group A). The second group included symptomatic PLHIV regardless of ART status or CD4 + T-cell count (Group B); all followed for 30 days. Detection of Histoplasma Ag (HisAg) in urine was done by enzyme immunoassay (EIA), Cryptococcus antigen (CrAg) was detected in serum and cerebrospinal fluid (CSF) specimens by lateral flow assay (LFA), and lipoarabinomannan (LAM) detection in urine was by LFA (TB LAM) and in sputum by GeneXpert for diagnosis of Mycobacterium infections. RESULTS: From August 2021 to June 2022, 491 PLHIV were enrolled; 482 (98%) had a CD4 + T-cell result, and 381 patients (79%) were classified with AHD according to CD4 + T-cell count (< 200 CD4/mm3). Frequency of an OI was 38% (n = 145/381). Antigen test positivity rate was 16% (72/467) for TB-LAM, 9% (43/464) for HisAg, and 11% (51/484) for CrAg. Twenty-one of 34 (62%) patients receiving CSF CrAg tests were positive, confirming meningitis. Significant differences in 30-day mortality were observed in patients with an OI (16%) vs. no OI (7%) (p = 0.002). Mortality was highest in patients with histoplasmosis (25%), co-infection (22%), cryptococcosis (18% overall; 19% for cryptococcal meningitis), and TB (10%). CONCLUSIONS: TB and fungal OIs, including co-infection, were common in PLHIV in Paraguay and had high associated mortality. Laboratories and health facilities need access to CD4 + T-cell testing and rapid diagnostic assays.

Incidence and Predicting Factors of Opportunistic Infections after Antiretroviral Therapy Initiation among Treatment-naïve Patients with HIV Infection: A Retrospective Cohort Study in A Tertiary Care Hospital.

OBJECTIVES: To determine the incidence of opportunistic infections (OIs) and the predictive factors for the development of OIs after antiretroviral therapy (ART) initiation among treatment-naïve patients with HIV infection. RESULTS: Of 401 HIV-infected patients, 38 (9.5%) HIV-infected patients developed OIs after initiating ART, with an incidence rate of 25.6/1000 person-years. The median time (IQR) from ART initiation to OI occurrence was 26.5 (14-73) days. In multivariate Cox proportional hazard regression, body mass index ≤18.5 kg/m2 (adjusted hazard ratio [aHR] 2.28, 95% confidence interval [CI] 1.18-4.42, P = .015), symptoms at presentation (aHR 13.59, 95% CI 3.24-56.9, P < .001), serum glutamate-pyruvate transaminase >55 U/L (aHR 2.09, 95% CI 1.06-4.15, P = .035), and initiation of a dolutegravir-based regimen (aHR 4.39, 95% CI 1.54-12.48, P = .006) were significantly associated with OIs after ART initiation. CONCLUSION: OIs after ART initiation are common. Malnutrition, symptomatic presentation, abnormal liver enzymes, and DTG-based regimens are predictors of OI occurrence after ART initiation. Physicians must monitor and appropriately treat OIs after ART initiation.

Adhesion of Klebsiella oxytoca to bladder or lung epithelial cells is promoted by the presence of other opportunistic pathogens.

The intestinal and respiratory tracts of healthy individuals serve as habitats for a diverse array of microorganisms, among which Klebsiella oxytoca holds significance as a causative agent in numerous community- and hospital-acquired infections, often manifesting in polymicrobial contexts. In specific circumstances, K. oxytoca, alongside other constituents of the gut microbiota, undergoes translocation to distinct physiological niches. In these new environments, it engages in close interactions with other microbial community members. As this interaction may progress to co-infection where the virulence of involved pathogens may be promoted and enhance disease severity, we investigated how K. oxytoca affects the adhesion of commonly co-isolated bacteria and vice versa during co-incubation of different biotic and abiotic surfaces. Co-incubation was beneficial for the adhesion of at least one of the two co-cultured strains. K. oxytoca enhanced the adhesion of other enterobacteria strains to polystyrene and adhered more efficiently to bladder or lung epithelial cell lines in the presence of most enterobacteria strains and S. aureus. This effect was accompanied by bacterial coaggregation mediated by carbohydrate-protein interactions occurring between bacteria. These interactions occur only in sessile, but not planktonic populations, and depend on the features of the surface. The data are of particular importance for the risk assessment of the urinary and respiratory tract infections caused by K. oxytoca, including those device-associated. In this paper, we present the first report on K. oxytoca ability to acquire increased adhesive capacities on epithelial cells through interactions with common causal agents of urinary and respiratory tract infections.

[Lomentospora prolificans Fungemia in a Patient With T-Cell Large Granular Leukemia: A Rare Pathogen in Türkiye]. / T-hücreli Büyük Granüler Lösemili Bir Hastada Lomentospora prolificans Fungemisi: Türkiye'de Nadir Bir Etken.

Scedosporium/Lomentospora is an opportunistic fungal pathogen found worldwide. While Scedosporium apiospermum and Scedosporium boydii are commonly observed globally, Lomentospora prolificans, which mainly affects immunosuppressed individuals, is rarely encountered and is more prevalent in arid climates, particularly in Australia and Spain. L.prolificans is a fungus commonly found in environmental sources such as contaminated water and soil. This species is known as an opportunistic pathogen that can cause deep-seated fungal infections, especially in immunosuppressed individuals. In this case report, a fatal case of L.prolificans fungemia in a patient with T-cell large granular leukemia during profound neutropenia was presented. The patient admitted to the hospital with prolonged fever, neutropenia, and shortness of breath. Antibiotherapy was administered to the patient for febrile neutropenia, but the fever persisted and his clinical status rapidly deteriorated. L.prolificans was isolated from the blood culture, and considering its antifungal resistance, combination therapy of voriconazole and terbinafine was initiated. However, the patient died of septic shock and multiple organ failure. In conclusion, although L.prolificans infections are rare, they can be life-threatening, especially in immunosuppressed individuals. Diagnosis and treatment of such infections may be difficult, therefore rapid diagnostic methods and appropriate treatment protocols should be developed. Consideration of infections caused by rare fungal pathogens in patients with risk factors may be critical for patient care. The literature review revealed that the first case of L.prolificans fungemia from Türkiye was reported in 2023. This case presentation represents the second reported case. However, in our case, L.prolificans fungemia occurred in 2018, it can be considered that L.prolificans may have been an invasive fungal pathogen of significant concern in Türkiye much earlier than previously documented.

[Infection prevention in secondary immunodeficiencies]. / Preventie van infecties bij verworven afweerstoornis.

Over one million people in The Netherlands are estimated having an immunodeficiency, of which the majority has an acquired immunodeficiency due to immunosuppressive medication. These patients are at risk for a more severe course of common infections, and also for opportunistic infections and viral reactivations. The following topics are discussed: types of immunodeficiency and how to estimate its severity; commonly seen infections in immunocompromised patients; recommended screening before start of immunosuppressive medication; pitfalls in clinical clues and diagnostics, and safety and immunogenicity of vaccination in these patients. Conclusively, recognition of an immunodeficiency and awareness of the risks and preventive measures are required. This article attempts to provide a pragmatic classification on the infection risk per type of immunosuppressive medication for clinical practice.

Exploring the association between erythema multiforme and HIV infection: some mechanisms and implications.

Erythema multiforme (EM) is an immune-mediated mucocutaneous condition characterized by hypersensitivity reactions to antigenic stimuli from infectious agents and certain drugs. The most commonly implicated infectious agents associated with EM include herpes simplex virus (HSV) and Mycoplasma pneumoniae. Other infectious diseases reported to trigger EM include human immunodeficiency virus (HIV) infection and several opportunistic infections. However, studies focusing on EM and human immunodeficiency virus (HIV) infection are scarce. even though the incidence of EM among HIV-infected individuals have increased, the direct and indirect mechanisms that predispose HIV-infected individuals to EM are not well understood. In turn, this makes diagnosing and managing EM in HIV-infected individuals an overwhelming task. Individuals with HIV infection are prone to acquiring microorganisms known to trigger EM, such as HSV, Mycobacterium tuberculosis, Treponema pallidum, histoplasmosis, and many other infectious organisms. Although HIV is known to infect CD4 + T cells, it can also directly bind to the epithelial cells of the oral and genital mucosa, leading to a dysregulated response by CD8 + T cells against epithelial cells. HIV infection may also trigger EM directly when CD8 + T cells recognize viral particles on epithelial cells due to the hyperactivation of CD8 + T-cells. The hyperactivation of CD8 + T cells was similar to that observed in drug hypersensitivity reactions. Hence, the relationship between antiretroviral drugs and EM has been well established. This includes the administration of other drugs to HIV-infected individuals to manage opportunistic infections. Thus, multiple triggers may be present simultaneously in HIV-infected individuals. This article highlights the potential direct and indirect role that HIV infection may play in the development of EM and the clinical dilemma that arises in the management of HIV-infected patients with this condition. These patients may require additional medications to manage opportunistic infections, many of which can also trigger hypersensitivity reactions leading to EM.

An opportunistic pathogen under stress: how Group B Streptococcus responds to cytotoxic reactive species and conditions of metal ion imbalance to survive.

Group B Streptococcus (GBS; also known as Streptococcus agalactiae) is an opportunistic bacterial pathogen that causes sepsis, meningitis, pneumonia, and skin and soft tissue infections in neonates and healthy or immunocompromised adults. GBS is well-adapted to survive in humans due to a plethora of virulence mechanisms that afford responses to support bacterial survival in dynamic host environments. These mechanisms and responses include counteraction of cell death from exposure to excess metal ions that can cause mismetallation and cytotoxicity, and strategies to combat molecules such as reactive oxygen and nitrogen species that are generated as part of innate host defence. Cytotoxicity from reactive molecules can stem from damage to proteins, DNA, and membrane lipids, potentially leading to bacterial cell death inside phagocytic cells or within extracellular spaces within the host. Deciphering the ways in which GBS responds to the stress of cytotoxic reactive molecules within the host will benefit the development of novel therapeutic and preventative strategies to manage the burden of GBS disease. This review summarizes knowledge of GBS carriage in humans and the mechanisms used by the bacteria to circumvent killing by these important elements of host immune defence: oxidative stress, nitrosative stress, and stress from metal ion intoxication/mismetallation.