Granulomatous Pneumocystis jiroveci pneumonia associated with immune reconstituted HIV

Advances in cellular and tissue-based imaging techniques for sarcoid granulomas

Sarcoidosis embodies a complex inflammatory disorder spanning multiple systems, with its origin remaining elusive. It manifests as the infiltration of inflammatory cells that coalesce into distinctive noncaseous granulomas within afflicted organs. Unraveling this disease necessitates the utilization of cellular or tissue-based imaging methods to both visualize and characterize the biochemistry of these sarcoid granulomas. Although hematoxylin and eosin stain, standard in routine use alongside cytological stains have found utility in diagnosis within clinical contexts, special stains such as Masson's trichrome, reticulin, methenamine silver, and Ziehl-Neelsen provide additional varied perspectives of sarcoid granuloma imaging. Immunohistochemistry aids in pinpointing specific proteins and gene expressions further characterizing these granulomas. Finally, recent advances in spatial transcriptomics promise to divulge profound insights into their spatial orientation and three-dimensional (3-D) molecular mapping. This review focuses on a range of preexisting imaging methods employed for visualizing sarcoid granulomas at the cellular level while also exploring the potential of the latest cutting-edge approaches like spatial transcriptomics and matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI), with the overarching goal of shedding light on the trajectory of sarcoidosis research.

Granulomatous Pneumocystis jiroveci Pneumonia in an HIV-Positive Patient on Antiretroviral Therapy: A Diagnostic Challenge

Human Immunodeficiency Virus (HIV)-related Opportunistic Infections (OI), including Pneumocystis jiroveci pneumonia (PCP), have become much less commonplace with anti-retroviral therapy (ART). Despite this, OIs are still common and it is important to remain vigilant for their presence and be aware of how ART and OI chemoprophylaxis may lead to atypical disease presentations. We present the case of a 51-year-old woman with HIV and CD4+ T helper lymphocytes cell count > 200 cells/ul on both ART and trimethoprim/sulfamethoxazole prophylaxis who presented with cavitating lung masses, mediastinal lymphadenopathy and pleural effusions. Negative bronchoalveolar lavage (BAL) and transbronchial biopsy (TBBx) prompted a second diagnostic procedure with a transthoracic core needle biopsy; the final diagnosis was granulomatous PCP. This case showcases a very rare presentation of PCP, with both large cavitating lung masses on imaging and granulomatous reaction on pathology, as well as the challenge of a potentially missed diagnosis with negative BAL and TBBx requiring transthoracic core needle biopsy for a final diagnosis.

High-resolution CT, histopathologic, and clinical features of granulomatous pneumocystis jiroveci pneumonia

Although pneumocystis jiroveci pneumonia was historically associated with HIV/AID patients, there is a recent shift in demographics with increasing incidence in patients with hematologic malignancies and transplants. A granulomatous response to pneumocytis jiroveci infection is uncommon and most commonly presents as multiple randomly distributed nodules on chest imaging. Granulomatous pneumocytis jiroveci pneumonia presents with similar clinical manifestations as typical pneumocytis pneumonia but is usually not detected by bronchoalveolar lavage and may require biopsy for a definitive diagnosis. For this reason, the radiologist may be the first provider to suggest this diagnosis and guide management.

Nodular granulomatous Pneumocystis jiroveci pneumonia consequent to delayed immune reconstitution inflammatory syndrome

Although Pneumocystis jiroveci pneumonia (PCP) is a frequent manifestation of acquired immune deficiency syndrome (AIDS), the granulomatous form is uncommon. Here, we present an unusual case of granulomatous PCP consequent to immune reconstitution inflammatory syndrome (IRIS) after highly active antiretroviral therapy. A 36-year-old woman with human immunodeficiency virus (HIV) presented with cough and dyspnea that were attributed to typical PCP associated with AIDS. She was successfully treated with antibiotic, steroid, and antiretroviral therapies. After six months, however, she presented with consolidating lung lesions caused by bronchial obstruction from PCP granulomatous disease. Although antibiotics were ineffective, the effectiveness of steroid therapy suggested a diagnosis of granulomatous IRIS caused by persistent PCP antigens. Physicians should strongly suspect PCP in HIV-positive patients with nodular lung lesions and must remain aware that these lesions, if immune in origin, might not respond to antimicrobial therapy.

Immune reconstitution inflammatory syndrome in HIV-infected patients with Pneumocystis jirovecii pneumonia

INTRODUCTION

The incidence of immune reconstitution inflammatory syndrome (IRIS) in HIV-infected patients after an episode of Pneumocystis jirovecii pneumonia (PJP) seems to be lower than with other opportunistic infections. We conducted an observational study in order to determine the incidence, clinical characteristics and outcome of patients diagnosed with PJP-related IRIS.

METHODS

We conducted an observational study of HIV patients diagnosed with PJP-related IRIS from January 2000 to November 2015. We analyzed epidemiological and clinical characteristics as well as laboratory findings. We also carried out a systematic review of published cases.

RESULTS

Six cases of IRIS out of 123 (4.9%) HIV-infected patients with PJP who started ART were diagnosed. All six cases were men with a median age of 34 (IQR: 8) years. The six patients developed paradoxical IRIS. Subjects younger than 40 years old (p=0.084) and with an HIV-RNA viral load >100000 copies/ml (p=0.081) at diagnosis showed a tendency to develop IRIS. Thirty-seven published cases of PJP-related IRIS were identified. Although 51% of cases involved respiratory failure, no deaths were reported.

CONCLUSIONS

PJP-related IRIS is rare condition compared to other opportunistic infections. It can lead to a severe respiratory failure in a significant proportion of cases, although no deaths have been reported.

Unmasking Granulomatous Pneumocystis jirovecii Pneumonia with Nodular Opacity in an HIV-Infected Patient after Initiation of Antiretroviral Therapy

Pneumocystis jirovecii pneumonia (PJP) in patients with HIV infection can, in rare cases, present with pulmonary nodules that histologically involve granulomatous inflammation. This report describes an intriguing case of granulomatous PJP with pulmonary nodules after commencing antiretroviral therapy (ART) in an HIV-infected patient without respiratory signs or symptoms. Diagnosis of granulomatous PJP was only achieved through thoracoscopic lung biopsy. This case suggests that granulomatous PJP should be considered in the differential diagnosis of pulmonary nodules in HIV-infected patients for unmasking immune reconstitution inflammatory syndrome manifestation after initiation of ART.

Early development of immune reconstitution inflammatory syndrome related to Pneumocystis pneumonia after antiretroviral therapy

Immune reconstitution inflammatory syndrome is a recognized complication after the initiation of combination antiretroviral therapy (cART). We report a patient who developed life-threatening pulmonary immune reconstitution inflammatory syndrome (IRIS) three days after initiation of cART. We reviewed published cases of IRIS after Pneumocystis pneumonia (PCP), in particular the time from initiation of cART to IRIS event. The median duration from the initiation of cART to the onset of IRIS was 15 days in the 33 patients reviewed. This report alerts clinicians to the rapidity of the development of pulmonary IRIS following PCP after the initiation of cART.