Factors Associated with Pneumocystis jirovecii Pneumonia in Patients with Rheumatoid Arthritis Receiving Methotrexate: A Single-center Retrospective Study

Effectiveness and safety of lower dose sulfamethoxazole/trimethoprim for Pneumocystis jirovecii pneumonia prophylaxis in patients with systemic rheumatic diseases receiving moderate-to high-dose glucocorticoids

OBJECTIVES

To compare the effectiveness and safety of low-dose sulfamethoxazole/trimethoprim (SMX/TMP) for Pneumocystis jirovecii pneumonia (PCP) prophylaxis in patients with systemic rheumatic disease (SRD) who were receiving glucocorticoids.

METHODS

We retrospectively analyzed data obtained from Japanese patients with SRD who received glucocorticoids between January 2006 and April 2024. Patients were divided into two groups based on the initial dose of SMX/TMP: low-dose (one tablet twice weekly on non-consecutive days); conventional-dose (one tablet per day). The primary endpoint was the incidence of PCP after 1 year since the initiation of SMX/TMP. Secondary endpoints were discontinuation rates of SMX/TMP therapy and severe adverse drug reactions (ADRs) after 1 year since the initiation of SMX/TMP in both groups, before and after adjusting for patient characteristics.

RESULTS

A total of 186 patients were included in this study: 60 in the low-dose group and 126 in the conventional-dose group. No patients developed PCP within one year after starting SMX/TMP; however, two patients in the low-dose group required escalation of the SMX/TMP dose to the conventional dose due to subclinical PCP. In the adjusted analysis, the low-dose group had a significantly lower discontinuation rate and a lower incidence rate of severe ADRs than the conventional-dose group.

CONCLUSIONS

Lower-dose SMX/TMP therapy was as effective as conventional therapy for PCP prophylaxis and was associated with lower discontinuation rates in patients with SRD receiving glucocorticoids.

Pneumocystis jirovecii Pneumonia in HIV-Negative, Non-transplant Patients: Epidemiology, Clinical Manifestations, Diagnosis, Treatment, and Prevention

Purpose of Review

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic fungal infection that is increasingly seen in HIV-negative patients with immune compromise due to other etiologies. We lack comprehensive clinical recommendations for this population.

Recent Findings

In non-HIV cases, PJP has a mortality rate of up to 50%, which is unacceptable despite the presence of safe and effective prophylaxis and therapy. Steroid use is one of the most common risk factors for disease development. New data suggests that lower doses of the preferred treatment regimen, TMP-SMX, may be equally effective for treatment while limiting side effects. While commonly used, the benefit of corticosteroids for the treatment of PJP has recently been called into question, with a recent multicenter cohort demonstrating no benefit among solid organ transplant recipients.

Summary

A high suspicion of PJP in individuals with pneumonia during immunosuppressant use is crucial. Therapeutic options are evolving to decrease potential side effects while maintaining efficacy in this highly morbid disease.

Comparison of the outcomes of Pneumocystis jirovecii pneumonia in rheumatoid arthritis patients treated with and without biologics

BACKGROUND

To investigate the outcomes of Pneumocystis jirovecii pneumonia (PCP) between patients with rheumatoid arthritis (RA) treated with and without biologics before PCP onset.

PATIENTS AND METHODS

We retrospectively included rheumatoid arthritis (RA) patients with PCP treated with and without biologics before PCP onset. The primary endpoints were 30-day and 180-day survival rates, and the secondary endpoint was severe PCP, including in-hospital death, intensive care unit admission, and requirement of respiratory support during hospitalization.

RESULTS

Eighty-two patients were enrolled in this study, including the Biologics group (n = 39) and Non-Biologics group (n = 43). There were no significantly differences in the 30-day and 180-day survival rates and severe PCP rate in the Biologics group and the Non-Biologics group before and after adjusting the patient characteristics. Kaplan-Meier survival curves for death showed no significantly differences between the Biologics and Non-Biologics groups. Cox regression hazard analysis revealed that the average daily prednisolone dose within 90 days before PCP onset was weakly associated with mortality after PCP.

CONCLUSIONS

Biologic use before PCP onset did not increase the severity and mortality of PCP compared to non-biologics use in patients with RA.

A Rare Case of Drug Reaction with Eosinophilia and Systemic Symptoms Syndrome Leading to Hemodialysis and Multiple Infections: A Case Report and Literature Review

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a severe drug eruption that causes multiple organ damage. The renal impairment in these patients usually improves with immunosuppressants, but subsequent infections often develop. We herein report a rare case of DRESS syndrome leading to hemodialysis and multiple infections with Pneumocystis pneumonia, cytomegalovirus and Aspergillus despite the administration of low-dose prednisolone. We also present a literature review of cases requiring dialysis after DRESS syndrome. In patients with chronic kidney disease, it is important to be alert for not only the development of DRESS syndrome but also subsequent infections.

Deep mutational scanning of Pneumocystis jirovecii dihydrofolate reductase reveals allosteric mechanism of resistance to an antifolate

Pneumocystis jirovecii is a fungal pathogen that causes pneumocystis pneumonia, a disease that mainly affects immunocompromised individuals. This fungus has historically been hard to study because of our inability to grow it in vitro. One of the main drug targets in P. jirovecii is its dihydrofolate reductase (PjDHFR). Here, by using functional complementation of the baker's yeast ortholog, we show that PjDHFR can be inhibited by the antifolate methotrexate in a dose-dependent manner. Using deep mutational scanning of PjDHFR, we identify mutations conferring resistance to methotrexate. Thirty-one sites spanning the protein have at least one mutation that leads to resistance, for a total of 355 high-confidence resistance mutations. Most resistance-inducing mutations are found inside the active site, and many are structurally equivalent to mutations known to lead to resistance to different antifolates in other organisms. Some sites show specific resistance mutations, where only a single substitution confers resistance, whereas others are more permissive, as several substitutions at these sites confer resistance. Surprisingly, one of the permissive sites (F199) is without direct contact to either ligand or cofactor, suggesting that it acts through an allosteric mechanism. Modeling changes in binding energy between F199 mutants and drug shows that most mutations destabilize interactions between the protein and the drug. This evidence points towards a more important role of this position in resistance than previously estimated and highlights potential unknown allosteric mechanisms of resistance to antifolate in DHFRs. Our results offer unprecedented resources for the interpretation of mutation effects in the main drug target of an uncultivable fungal pathogen.

Risk factors for invasive fungal infections in patients with connective tissue disease: Systematic review and meta-analysis

OBJECTIVE

Invasive fungal infections (IFIs) are life-threatening opportunistic infections in patients with connective tissue disease CTD) that cause significant morbidity and mortality. We attempted to determine the potential risk factors associated with IFIs in CTD.

METHODS

We systematically searched PubMed, Embase, and the Cochrane Library databases for relevant articles published from the database inception to February 1, 2023.

RESULTS

Twenty-six studies were included in this systematic review and meta-analysis. Risk factors identified for IFIs were diabetes (odds ratio [OR], 1.62; 95% confidence interval [CI], 1.00 to 2.64), pulmonary diseases (OR 3.43; 95% CI 2.49 to 4.73), interstitial lung disease (ILD; OR, 4.06; 95% CI, 2.22 to 7.41), renal disease (OR, 4.41; 95% CI, 1.84 to 10.59), glucocorticoid (GC) use (OR, 4.15; 95% CI, 2.74 to 6.28), especially moderate to high-dose GC, azathioprine (AZA) use (OR, 1.50; 95% CI, 1.12 to 2.01), calcineurin inhibitor (CNI) use (OR, 2.49; 95% CI, 1.59 to 3.91), mycophenolate mofetil (MMF) use (OR, 2.83; 95% CI, 1.59 to 5.03), cyclophosphamide (CYC) use (OR, 3.35; 95% CI, 2.47 to 4.54), biologics use (OR, 3.43; 95% CI, 2.36 to 4.98), and lymphopenia (OR, 4.26; 95% CI, 2.08 to 8.73). Hydroxychloroquine (HCQ) use reduced risk of IFIs (OR, 0.67; 95% CI, 0.54 to 0.84). Furthermore, 17 of the 26 studies only reported risk factors for Pneumocystis jiroveci pneumonia (PJP) in patients with CTD. Pulmonary disease; ILD; and the use of GC, CNIs, CYC, methotrexate (MTX), MMF and biologics, and lymphopenia increased the risk of PJP, whereas the use of HCQ reduced its risk.

CONCLUSION

Diabetes, pulmonary disease, ILD, renal disease, use of GC (especially at moderate to high dose) and immunosuppressive drugs, and lymphopenia were found to be associated with significant risk for IFIs (especially PJP) in patients with CTD. Furthermore, the use of HCQ may reduce the risk of IFIs in patients with CTD.

A Case of Severe Pneumocystis Pneumonia in an HIV-Negative Patient Successfully Treated with Oral Atovaquone

Currently, atovaquone is not recommended for treating severe Pneumocystis jirovecii pneumonia (PCP) due to insufficient evidence in clinical studies. This report describes a case of severe PCP in a human immunodeficiency virus (HIV)-negative immunosuppressed patient who was successfully treated with oral atovaquone and corticosteroids. A 63-year-old Japanese woman complained of fever and dyspnea for 3 days. She had been treated with oral prednisolone (30 mg/day) for interstitial pneumonia for 3 months without PCP prophylaxis. Although we could not confirm P. jirovecii from the respiratory specimen, a diagnosis of PCP was indicated by marked elevation of serum beta-D-glucan levels and bilateral ground-glass opacities in the lung fields. Based on the arterial blood gas test results (alveolar-arterial oxygen difference >45 mmHg), the disease status of PCP was defined as severe. Trimethoprim-sulfamethoxazole (SXT) is the first-line drug for treating severe PCP. However, given the patient's history of SXT-induced toxic epidermal necrolysis, she was administered atovaquone instead of SXT. Her clinical symptoms and respiratory condition gradually improved, with a 3-week treatment showing a good clinical course. Previous clinical studies on atovaquone have only been conducted in HIV-positive patients with mild or moderate PCP. Accordingly, the clinical efficacy of atovaquone for severe PCP cases or PCP in HIV-negative patients remains unclear. There is a rising incidence of PCP among HIV-negative patients, given the increasing number of patients receiving immunosuppressive medications; moreover, atovaquone has less severe side effects than SXT. Therefore, there is a need for further clinical investigation to confirm the efficacy of atovaquone in cases of severe PCP, especially among HIV-negative patients. In addition, it also remains unclear whether corticosteroids are beneficial for severe PCP in non-HIV patients. Thus, the use of corticosteroids in cases of severe PCP in non-HIV patients should also be investigated.

Safety of synthetic and biological DMARDs: a systematic literature review informing the 2022 update of the EULAR recommendations for the management of rheumatoid arthritis

OBJECTIVES

To perform a systematic literature review (SLR) concerning the safety of synthetic(s) and biological (b) disease-modifying antirheumatic drugs (DMARDs) to inform the 2022 update of the EULAR recommendations for the management of rheumatoid arthritis (RA).

METHODS

SLR of observational studies comparing safety outcomes of any DMARD with another intervention in RA. A comparator group was required for inclusion. For treatments yet without, or limited, registry data, randomised controlled trials (RCTs) were used.

RESULTS

Fifty-nine observational studies addressed the safety of DMARDs. Two studies (unclear risk of bias (RoB)) showed an increased risk of serious infections with bDMARDs compared with conventional synthetic (cs)DMARDs. Herpes zoster infections occurred more with JAKi than csDMARDs (adjusted HR (aHR): 3.66) and bDMARDs (aHR: 1.9-2.3) (four studies, two low RoB). The risk of malignancies was similar across bDMARDs (five studies) and with tofacitinib compared with bDMARDs (one study, low RoB). The risk of major adverse cardiovascular events (MACE) was similar with bDMARDs and tofacitinib (two studies, one low RoB). Thirty studies reported safety from RCTs, with one, designed to evaluate safety, showing that malignancies (HR (95% CI): 1.48 (1.04 to 2.09)) and MACE (HR (95% CI): 1.33 (0.91 to 1.94)) occurred numerically more frequently with tofacitinib (5 mg and 10 mg doses combined) than with TNFi in patients with cardiovascular risk factors. In this study, the risk of venous thromboembolism (VTE) was higher with tofacitinib 10 mg than with TNFi.

CONCLUSION

The safety profile of bDMARDs was further demonstrated. Whether the difference in incidence of malignancies, MACE and VTE between tofacitinib and TNFi applies to other JAKi needs further evaluation.

Outcomes and Risk Factors for Mortality in Pneumocystis Pneumonia Patients with Rheumatoid Arthritis: A Multicenter Retrospective Cohort Study

OBJECTIVE

To evaluate outcomes and risk factors for death in patients with rheumatoid arthritis (RA) who developed Pneumocystis pneumonia (PCP).

METHODS

: We included RA patients who were diagnosed with PCP at seven participating community hospitals between July 2005 and October 2020. Clinical features were compared between survivors and non-survivors. Disease-modifying antirheumatic drugs (DMARDs) before PCP onset and after PCP recovery were also examined.

RESULTS

Seventy RA patients developed PCP, and among them, 60 (85.7%) received methotrexate (MTX) monotherapy (40%) or MTX combination therapy with other DMARDs (45.7%). PCP was more likely to occur after 12 months of MTX monotherapy and within 3 months of MTX combination therapy. Thirteen patients (18.6%) died despite PCP treatment. Multivariable logistic regression analysis revealed that coexisting RA-associated interstitial lung disease (RA-ILD; odds ratio [OR] 6.18, 95% confidence interval [CI] 1.17-32.63) and delayed PCP treatment with anti-Pneumocystis drugs (OR 15.29, 95% CI 1.50-156.15) are significant risk factors for PCP mortality in RA patients. Most survivors successfully resumed DMARD therapy without PCP prophylaxis; one recurrent PCP case was observed during follow-up (median, 4.1 years).

CONCLUSION

To avoid a treatment delay, RA patients should be followed-up for signs and symptoms of PCP development, especially those with RA-ILD.