Merkel Cell Carcinoma Mimicking a Pyogenic Granuloma on the Thumb

Merkel cell carcinoma (MCC) is a rare and aggressive skin cancer that can present with various clinical manifestations. An 80-year-old male, known to have chronic lymphocytic leukaemia presented with a lesion on his left thumb, initially thought to be a pyogenic granuloma. The lesion was cauterized with silver nitrate but remained persistent. A curettage biopsy was performed, and a histopathological examination revealed MCC. The patient was subsequently referred to dermatology and plastic surgery for further management. The lesion was excised; a full-thickness skin graft was used to close the defect. This case highlights the importance of considering MCC in the differential diagnosis of skin lesions, even if they present with a benign appearance.

Silicone Cervical Lymphadenopathy: A Rare Complication After Breast Augmentation

A 66-year-old female patient, who had undergone breast augmentation 10 years ago, presented with unilateral neck pain, dysphagia, and hoarseness. Subsequent imaging revealed right-sided supraclavicular and axillary lymphadenopathy and a breast implant rupture on the same side. A lymph node core biopsy under sonographic guidance revealed silicone lymphadenopathy. Implant extirpation was offered to the patient. Cervical lymphadenopathy warrants an initial workup to exclude sinister chronic inflammatory or malignant conditions. Nonetheless, in cases of diagnostic uncertainty and a history of breast augmentation, the otolaryngologist should be cognizant of distal silicone lymphadenopathy. This condition is associated with silicone leakage and lymphatic dissemination of silicone particles. Even though silicone-related granuloma formation is a rare entity, its incidence is slowly rising as the population that has undergone breast augmentation grows older.

Mycobacterium tuberculosis Resides in Macrophages in Laryngeal Tuberculosis: A Case Report

Laryngeal tuberculosis is a rare form of extrapulmonary tuberculosis that questions the natural history of this infection. We report one such case in which a pathological examination of a laryngeal biopsy revealed granulomatous inflammation with caseous necrosis. Further investigations combining immunofluorescence detection of macrophages and in situ hybridization of Mycobacterium tuberculosis indicated the presence of Mycobacterium tuberculosis (M. tuberculosis) in laryngeal granulomatous inflammatory lesions. This observation suggests that the natural history of laryngeal tuberculosis does not differ from that of other forms, guiding early diagnosis in patients with laryngeal lesions to ensure appropriate check-ups and treatment.

Spatial Transcriptomics Reveals Signatures of Histopathological Changes in Muscular Sarcoidosis

Sarcoidosis is a multisystemic disease characterized by non-caseating granuloma infiltrating various organs. The form with symptomatic muscular involvement is called muscular sarcoidosis. The impact of immune cells composing the granuloma on the skeletal muscle is misunderstood. Here, we investigated the granuloma-skeletal muscle interactions through spatial transcriptomics on two patients affected by muscular sarcoidosis. Five major transcriptomic clusters corresponding to perigranuloma, granuloma, and three successive muscle tissue areas (proximal, intermediate, and distal) around the granuloma were identified. Analyses revealed upregulated pathways in the granuloma corresponding to the activation of T-lymphocytes and monocytes/macrophages cytokines, the upregulation of extracellular matrix signatures, and the induction of the TGF-β signaling in the perigranuloma. A comparison between the proximal and distal muscles to the granuloma revealed an inverse correlation between the distance to the granuloma and the upregulation of cellular response to interferon-γ/α, TNF-α, IL-1,4,6, fibroblast proliferation, epithelial to mesenchymal cell transition, and the downregulation of muscle gene expression. These data shed light on the intercommunications between granulomas and the muscle tissue and provide pathophysiological mechanisms by showing that granuloma immune cells have a direct impact on proximal muscle tissue by promoting its progressive replacement by fibrosis via the expression of pro-inflammatory and profibrosing signatures. These data could possibly explain the evolution towards a state of disability for some patients.

Asymptomatic renal granuloma diagnosed 3 years after Bacillus Calmette-Guérin intravesical injection: A case report and a literature review

Introduction

Intravesical Bacillus Calmette-Guérin immunotherapy is an effective treatment for non-muscle-invasive bladder cancer, which is occasionally associated with side effects and complications. The incidence of significant renal complications after intravesical Bacillus Calmette-Guérin immunotherapy is less than 2%. We report a case of renal granuloma after intravesical Bacillus Calmette-Guérin immunotherapy for bladder cancer, which radiologically resembled a papillary renal cell carcinoma.

Case presentation

A 65-year-old man, who had a medical history of urothelial carcinoma and received intravesical Bacillus Calmette-Guérin therapy, was referred to our Urology Department with a right renal tumor. Imaging findings suggested papillary renal cell carcinoma. Robot-assisted partial nephrectomy was performed, and the histopathological examination revealed epithelioid cell granuloma, which were considered to be Bacillus Calmette-Guérin-related renal granuloma.

Conclusion

Bacillus Calmette-Guérin-related renal granuloma mimicking papillary renal cell carcinoma have been reported. We should consider the possibility of renal granulomas when encountering image abnormalities for patients treated with intravesical Bacillus Calmette-Guérin therapy.

Rubella virus-associated necrotizing granulomatous inflammation with extensive eyelid, ocular, and orbital involvement

We present a case of cutaneous granulomatous disease associated with rubella virus in a 4-year-old girl without an identifiable immunodeficiency. In this case, a combination of anti-inflammatory, anti-viral, and anti-neutrophil therapies successfully treated vision-threatening eyelid, conjunctival, scleral, and orbital inflammation.

High-Definition Videobronchoscopy for the Diagnosis of Airway Involvement in Sarcoidosis: The Enhance Sarcoidosis Multicenter Study

BACKGROUND

The ability of high-definition (HD) videobronchoscopy to detect airway involvement in sarcoidosis has not been evaluated previously.

RESEARCH QUESTION

What is the role of HD videobronchoscopy in the identification of sarcoidosis-associated airway abnormalities (AAs)? What are the patterns of AAs more commonly observed and more frequently associated with the detection of granulomas in endobronchial biopsy (EBB)?

STUDY DESIGN AND METHODS

In this prospective international multicenter cohort study, consecutive patients with suspected sarcoidosis underwent airway inspection with an HD videobronchoscope and EBB using a standardized workflow. AAs were classified according to six patterns defined a priori: nodularity, cobblestoning, thickening, plaque, increased vascularity, and miscellaneous. We assessed diagnostic yield of EBB, prevalence of AAs, and interobserver agreement for different patterns of AAs.

RESULTS

AAs were identified in 64 of 134 patients with sarcoidosis (47.8%), with nodularity (n = 23 [17.2%]), plaque (n = 19 [14.2%]), and increased vascularity (n = 19 [14.2%]) being the most prevalent. The diagnostic yield of EBB was 36.6%. AAs were significantly more prevalent in patients with than in those without nonnecrotizing granulomas on EBB (67.4% vs 36.5%; P = .001). Likewise, parenchymal disease on CT scan imaging was significantly more common in patients with than in those without nonnecrotizing granulomas on EBB (79.6% vs 54.1%; P = .003). On a per-lesion analysis, nonnecrotizing granulomas were seen especially in EBB samples obtained from areas of cobblestoning (9/10 [90%]) and nodularity (17/29 [58.6%]). The overall diagnostic yield of random EBB was low (31/134 [23.1%]). The interobserver agreement for the different patterns of AA was fair (Fleiss κ = 0.34).

INTERPRETATION

In a population with a large prevalence of White Europeans, HD videobronchoscopy detected AAs in approximately one-half of patients with sarcoidosis. The diagnostic yield of EBB was higher in patients with parenchymal involvement on CT scan imaging and in those with AAs, especially if manifesting as cobblestoning and nodularity.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT4743596; URL: www.

CLINICALTRIALS

gov.

Foreign Body Reaction Following Achilles Tendon Reconstruction With the Ligament Advanced Reconstructive System: Patient Outcomes and Clinical Course

The Ligament Advanced Reinforcement System (LARS) is a common choice for ligament reconstruction in the lower limb due to its good functional and quality of life (QoL)-related outcomes. It is commonly used for Achilles tendon repair following a rupture. While it facilitates tissue ingrowth and boasts good biocompatibility, we report on multiple cases whereby foreign body reactions have led to the growth of granulomas requiring surgical excision and Flexor Hallucis Longus (FHL) transfer. Following these cases, patients have been shown to have excellent functional and QoL-related outcomes using the Manchester Oxford Foot Questionnaire (MOX-FQ) and Foot and Ankle Ability Measure (FAAM). Surgeons should consider FHL transfer as an alternative in patients undergoing Achilles tendon repair and be aware of the risk of foreign body reactions and the impact on ankle function and QoL post-operatively.

Pediatric Gnathic Bony and Mesenchymal Tumors

Evaluation of bone pathology within the head and neck region, particularly the gnathic bonesis is complex, demonstrating unique pathologic processes. In part, this variation is due to odontogenesis and the embryological cells that may be involved, which can contribute to disease development and histologic variability. As with any boney pathosis, the key is to have clinical correlation, particularly with radiographic imaging prior to establishing a definitive diagnosis. This review will cover those entities that have a predilection for the pediatric population, and while it is not all inclusive, it should serve as a foundation for the pathologist who is evaluating bony lesions involving the craniofacial skeleton.

A Rare Case of Sarcoidosis Presenting as an Isolated Breast Mass and Pain: A Case Report and Literature Review

BACKGROUND Sarcoidosis is a benign systemic granulomatous disorder of unknown etiology that affects multiple organs. Patients diagnosed with sarcoidosis usually present with nonspecific symptoms: fatigue, fever, weight loss, and respiratory symptoms such as cough and dyspnea; 50% of the patients are asymptomatic at the time of diagnosis. In 90% of patients, sarcoidosis targets hilar and mediastinal lymph nodes. In rare cases, it presents solely in the breast with no other symptoms. The diagnosis is established based on compatible clinical and radiological findings and supported by histological evidence in 1 or more organs of non-caseating epithelioid cell granulomas in the absence of organisms or particles. CASE REPORT We herein present a unique case of a 27-year-old woman who presented with pain and swelling in her left breast. On examination, the left breast revealed multiple, firm-hard, and tender masses. Breast ultrasound showed large loculated focally dilated ducts with significant periductal vascularity and inflammation. Fine-needle aspiration (FNA) showed an inflammatory process with granulomatous formation. An ultrasound-guided core biopsy, which was histologically consistent with granulomatous mastitis, and elevated angiotensin-converting enzyme (ACE) levels confirmed a diagnosis of sarcoidosis. The patient was started on IV steroids followed by oral prednisolone and azathioprine. During treatment, the mass size decreased and the pain substantially improved. CONCLUSIONS It is important to consider sarcoidosis in a patient who presents with only pain and swelling in the breast to ensure early diagnosis and initiate treatment, improving the patient's overall prognosis.

Comparative pathology of experimental pulmonary tuberculosis in animal models

Research in human tuberculosis (TB) is limited by the availability of human tissues from patients, which is often altered by therapy and treatment. Thus, the use of animal models is a key tool in increasing our understanding of the pathogenesis, disease progression and preclinical evaluation of new therapies and vaccines. The granuloma is the hallmark lesion of pulmonary tuberculosis, regardless of the species or animal model used. Although animal models may not fully replicate all the histopathological characteristics observed in natural, human TB disease, each one brings its own attributes which enable researchers to answer specific questions regarding TB immunopathogenesis. This review delves into the pulmonary pathology induced by Mycobacterium tuberculosis complex (MTBC) bacteria in different animal models (non-human primates, rodents, guinea pigs, rabbits, cattle, goats, and others) and compares how they relate to the pulmonary disease described in humans. Although the described models have demonstrated some histopathological features in common with human pulmonary TB, these data should be considered carefully in the context of this disease. Further research is necessary to establish the most appropriate model for the study of TB, and to carry out a standard characterisation and score of pulmonary lesions.

Transcriptional profiling of a fungal granuloma reveals a low metabolic activity of Paracoccidioides brasiliensis yeasts and an actively regulated host immune response

Granulomas are important immunological structures in the host defense against the fungus Paracoccidioides brasiliensis, the main etiologic agent of Paracoccidioidomycosis (PCM), a granulomatous systemic mycosis endemic in Latin America. We have performed transcriptional and proteomic studies of yeasts present in the pulmonary granulomas of PCM aiming to identify relevant genes and proteins that act under stressing conditions. C57BL/6 mice were infected with 1x106 yeasts and after 8- and 12-weeks of infection, granulomatous lesions were obtained for extraction of fungal and murine RNAs and fungal proteins. Dual transcriptional profiling was done comparing lung cells and P. brasiliensis yeasts from granulomas with uninfected lung cells and the original yeast suspension used in the infection, respectively. Mouse transcripts indicated a lung malfunction, with low expression of genes related to muscle contraction and organization. In addition, an increased expression of transcripts related to the activity of neutrophils, eosinophils, macrophages, lymphocytes as well as an elevated expression of IL-1β, TNF-α, IFN-γ, IL-17 transcripts were observed. The increased expression of transcripts for CTLA-4, PD-1 and arginase-1, provided evidence of immune regulatory mechanisms within the granulomatous lesions. Also, our results indicate iron as a key element for the granuloma to function, where a high number of transcripts related to fungal siderophores for iron uptake was observed, a mechanism of fungal virulence not previously described in granulomas. Furthermore, transcriptomics and proteomics analyzes indicated a low fungal activity within the granuloma, as demonstrated by the decreased expression of genes and proteins related to energy metabolism and cell cycle.

Thoracic SMARCA4-deficient undifferentiated tumor with associated granulomatous reaction and response to pembrolizumab

Thoracic SMARCA4-deficient undifferentiated tumor (SMARCA4-UT) is a rare entity that was recently described in the current World Health Organization Classification of Tumors. These lesions are highly aggressive with dismal prognosis, and most patients present with metastasis at the time of diagnosis. While there are about 100 cases of SMARCA4-UT described in the literature, there are only few existing reports that describe the cytomorphology of these lesions. We present a patient with masses involving the mediastinum, right lung, right supraclavicular lymph node and right adrenal gland. Subsequent core-needle biopsy of the right supraclavicular lymph node showed epithelioid to pleomorphic tumor cells with prominent nucleoli and associated granulomatous inflammation. The tumor cells were positive for CD34 and synaptophysin, and were negative for cytokeratins. SMARCA4 and SMARCA2 both showed loss of expression, which led to the diagnosis of SMARCA4-UT. The patient underwent treatment with pembrolizumab (PD-1 blocker), carboplatin, etoposide, and radiotherapy, resulting in an almost 55% reduction in the size of the primary tumor. Our case illustrates that an associated granulomatous inflammation might be an uncommon presentation of an already rare malignancy, and awareness of this phenomenon would prevent from mistaking SMARCA4-UT for other more well-known entities that can present with granulomas.

Association between Clinical/Radiographic Characteristics and Histopathological Diagnoses of Periapical Granuloma and Cyst

OBJECTIVE

 The aim of this study was to determine the association between clinical/radiographic characteristics and histopathological diagnoses of periapical granuloma and cyst obtained from the teeth treated with endodontic microsurgery.

MATERIALS AND METHODS

 The clinical, radiographic (periapical and cone-beam computed tomography), and histopathological data were collected from patients' dental records of endodontic microsurgery on the teeth with periapical lesions. These lesions were histopathologically diagnosed as either granuloma or cyst, at the Endodontic Clinic, Faculty of Dentistry, Mahidol University, Bangkok, Thailand, from 2016 to 2021 according to inclusion and exclusion criteria. The data were analyzed using bivariate analysis and a multinomial logistic regression at a significance level of p-value less than 0.05.

RESULTS

 A total of 83 patients (58 females and 25 males) with an average age of 45 to 49.5 years old met the criteria including 68 periapical granulomas (81.9%) and 15 periapical cysts (18.1%). A periapical lesion involving multiple teeth in a periapical radiograph was significantly associated with the histopathological diagnosis of periapical cyst (p < 0.05). Such periapical lesion was six times more likely to be periapical cyst than periapical granuloma.

CONCLUSIONS

 A significant factor for predicting periapical cyst from periapical granuloma was the presence of a periapical lesion with multiple-teeth involvement in a dental radiograph.

Unusual Differences in the Pulmonary Histopathology of Mice after Intranasal Infection with Mycelial Propagules of Histoplasma capsulatum Strains Classified as LAm A2 and NAm 2 Phylogenetic Species

The ascomycete Histoplasma capsulatum is the causative agent of systemic respiratory mycosis histoplasmosis, which sometimes develops acute disseminated or chronic clinical forms, with the latter usually associated with granuloma formation. The present report shows differential histopathological changes in the pulmonary inflammatory response of mice infected intranasally with the mycelial morphotype of H. capsulatum strains with distinct genotypes, EH-46 and G-217B, classified as LAm A2 and NAm 2 phylogenetic species, respectively. Infected male BALB/c mice were sacrificed at different postinfection times, and their serial lung sections were stained with periodic acid-Schiff and analyzed via microscopy. In mice infected with the LAm A2 strain, the results showed progressive changes in the inflammatory infiltrate of the lung parenchyma during the first hours and days postinfection as well as granulomas with macrophages containing intracellular yeast cells, which prevailed at 14 and 21 days postinfection. Bronchiolar-associated lymphoid tissue was induced in mice infected with both strains, primarily in mice infected with the NAm 2 strain. Several lung sections from mice infected with the LAm A2 strain showed PAS-positive yeast cells aggregated in a perinuclear crown-like arrangement in macrophages from 3 h to 21 days postinfection. These findings highlight differences in the host pulmonary inflammatory response associated with distinct H. capsulatum species.

Characterisation and development of histopathological lesions in a guinea pig model of Mycobacterium tuberculosis infection

Tuberculosis (TB) remains a very significant infectious disease worldwide. New vaccines and therapies are needed, even more crucially with the increase of multi-drug resistant Mycobacterium tuberculosis strains. Preclinical animal models are very valuable for the development of these new disease control strategies. Guinea pigs are one of the best models of TB, sharing many features with the pathology observed in human TB. Here we describe the development of TB lesions in a guinea pig model of infection. We characterise the granulomatous lesions in four developmental stages (I-IV), using histopathological analysis and immunohistochemical (IHC) techniques to study macrophages, T cells, B cells and granulocytes. The granulomas in the guinea pigs start as aggregations of macrophages and few heterophils, evolving to larger lesions showing central caseous necrosis with mineralisation and abundant acid-fast bacilli, surrounded by a rim of macrophages and lymphocytes in the outer layers of the granuloma. Multinucleated giant cells are very rare and fibrotic capsules are not formed in this animal model.

Lung microenvironments harbor Mycobacterium tuberculosis phenotypes with distinct treatment responses

Tuberculosis lung lesions are complex and harbor heterogeneous microenvironments that influence antibiotic effectiveness. Major strides have been made recently in understanding drug pharmacokinetics in pulmonary lesions, but the bacterial phenotypes that arise under these conditions and their contribution to drug tolerance are poorly understood. A pharmacodynamic marker called the RS ratio® quantifies ongoing rRNA synthesis based on the abundance of newly synthesized precursor rRNA relative to mature structural rRNA. Application of the RS ratio in the C3HeB/FeJ mouse model demonstrated that Mycobacterium tuberculosis populations residing in different tissue microenvironments are phenotypically distinct and respond differently to drug treatment with rifampin, isoniazid, or bedaquiline. This work provides a foundational basis required to address how anatomic and pathologic microenvironmental niches may contribute to long treatment duration and drug tolerance during the treatment of human tuberculosis.

Breast silicone implants' pericapsular impairment: current underdiagnosed status

Many complications related to silicone implants have been reported recently, from clinical symptoms manifestations to association with some specific types of cancer. During the early 2010s, it was believed that implants were biocompatible and inert to the human body and that gel bleeding/leakage events were rare and without repercussions for the human body. However, at the end of 2010s, several studies pointed out that gel bleeding was more frequent than previously believed, and the pathogenic potential of free silicone should not be ignored. The Food and Drug Administration recommends performing magnetic resonance imaging in asymptomatic patients 5-6 years after implant placement. The descriptors in the Breast Imaging and Reporting Data System lexicon seem outdated for classifying the new generations of implants with cohesive gel, which hinders the diagnosis of device complications. In this review, supported by our research data publications related to silicone implants for 6 years on a prospective study protocol, most of them being original articles, we summarized the main complications observed in clinical practice and discuss the impact of these changes on patients' outcomes focusing on the pericapsular space.

Myeloid Phenotypes in Tracheostomy-Associated Granulation Tissue

OBJECTIVE(S)

Tracheostomy-associated granulation tissue is a common, recurrent problem occurring secondary to chronic mucosal irritation. Although granulation tissue is composed of predominantly innate immune cells, the phenotype of monocytes and macrophages in tracheostomy-associated granulation tissue is unknown. This study aims to define the myeloid cell population in granulation tissue secondary to tracheostomy.

METHODS

Granulation tissue biopsies were obtained from 8 patients with tracheostomy secondary to laryngotracheal stenosis. Cell type analysis was performed by flow cytometry and gene expression was measured by quantitative real-time polymerase chain reaction. These methods and immunohistochemistry were used to define the monocyte/macrophage population in granulation tissue and were compared to tracheal autopsy control specimens.

RESULTS

Flow cytometry demonstrated macrophages (CD45+CD11b+) and monocytes (CD45+FSClow SSClow ) represent 23.2 ± 6% of the granulation tissue cell population. The M2 phenotype (CD206) is present in 77 ± 11% of the macrophage population and increased compared to the M1 phenotype (p = 0.012). Classical monocytes (CD45+CD14high CD16low ) were increased in granulation tissue compared to controls (61.2 ± 7% and 30 ± 8.5%, p = 0.038). Eighty-five percent of macrophages expressed pro-inflammatory S100A8/A9 and 36 ± 4% of macrophages co-localized CD169, associated with tissue-resident macrophages. M2 gene expression (Arg1/CD206) was increased in granulation tissue (3.7 ± 0.4, p = 0.035 and 3.5 ± 0.5, p = 0.047) whereas M1 gene expression (CD80/CD86) was similar to controls (p = 0.64, p = 0.3). Immunohistochemistry of granulation tissue demonstrated increased cells co-localizing CD11b and CD206.

CONCLUSIONS

M2 macrophages are the dominant macrophage phenotype in tracheostomy-associated granulation tissue. The role of this cell type in promoting ongoing inflammation warrants future investigation to identify potential treatments for granulation tissue secondary to tracheostomy.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:2346-2356, 2023.

Postoperative Aspergillus Endophthalmitis With Iris Granuloma: A Case Report

This report describes a rare case of a fungal iris granulomatous lesion in a 67-year-old female who underwent cataract surgery in the left eye and, one month later, developed culture-positive postoperative Aspergillus endophthalmitis. On initial presentation in the emergency room, slit-lamp examination of the left eye revealed subconjunctival hemorrhage, 360-degree subconjunctival hemorrhage, mild corneal edema with Descemet's folds, a deep anterior chamber with a fibrinous reaction causing pupillary membrane formation, and an in situ intraocular lens with no view of the fundus. A bright-scan (B-scan) ultrasound revealed mild vitreous opacities with a vitreal membrane, shallow choroidal detachment, and no significant retinal and choroid layer thickening. The patient was admitted into the anterior segment division for anterior chamber (AC) tap culture and AC washout for suspected retained cortical matter removal, intracameral antibiotics (vancomycin and ceftazidime), and IOL explantation in the left eye. The initial aqueous tap culture had no growth. Nine days later, repeat aqueous tap and pupillary membrane cultures were positive for Aspergillus spp. Intravitreal voriconazole was administered along with topical natamycin and amphotericin B eye drops. There was a resolution of the clinical picture, and three weeks later a rebound occurred, for which AC washout, pars plana vitrectomy (PPV), capsulectomy, and intravitreal vancomycin, ceftazidime, and voriconazole were given. A week later, the patient developed a fungal granuloma behind the iris, which was successfully managed with an AC washout, removal of the granuloma, and repeated intravitreal and intracameral voriconazole administration. The best-corrected visual acuity (BCVA) during the last visit was 20/80 in the affected eye, with a plan for a secondary IOL implant. Endophthalmitis is a rare but serious intraocular infection, with fungal endophthalmitis having a lower prevalence than bacterial endophthalmitis, which explains the lack of well-established guidelines for diagnosing and managing exogenous fungal endophthalmitis. This case highlights the rare presentation of post-cataract Aspergillus endophthalmitis with a fungal iris granuloma and demonstrates how the chronicity of this infection, along with surgical manipulation, may accelerate the seeding of these organisms into the anterior chamber structures.

Chronic Ulcer on the Tongue as a Manifestation of Histoplasmosis During Anti-tumor Necrosis Factor-Alpha (TNF-⍺) Inhibitor Therapy for Psoriasis

Anti-tumor necrosis factor-alpha (TNF-⍺) inhibitors are commonly used in the treatment of inflammatory conditions such as psoriasis. However, these agents lead to increased susceptibility to infections. We report a patient with reactivation of latent histoplasmosis six months after starting an anti-TNF-⍺ inhibitor for the treatment of psoriasis. Dermatologists should be aware of the risks associated with initiating therapy and maintain a low threshold of suspicion for this infection in patients on anti-TNF-⍺ inhibitors presenting with oral ulcers.

A Pattern-Based Approach to Hepatic Infections

The evaluation of liver biopsies for infection can be a challenging and frustrating situation for diagnostic pathologists as well as clinicians. Patients often present with nonspecific symptoms, such as fever and elevated transaminases, leading to a broad differential diagnosis that typically includes malignancy and noninfectious inflammatory diseases in addition to infections. A pattern-based histologic approach can be extremely helpful in both making a diagnosis and guiding the next steps for the evaluation of the pathology specimen as well as the patient. This review discusses several of the more commonly encountered histologic patterns associated with hepatic infectious diseases, the most common pathogens with which they are associated, and helpful ancillary studies.

Exome Sequencing Implicates DGKZ , ESRRA , and GXYLT1 for Modulating Granuloma Formation in Crohn Disease

Non-caseating granulomas may indicate a more aggressive phenotype of Crohn disease (CD). Genetic associations of granulomatous CD (GCD) may help elucidate disease pathogenesis. Whole-exome sequencing was performed on peripheral blood-derived DNA from 17 pediatric patients with GCD and 19 with non-GCD (NGCD), and from an independent validation cohort of 44 GCD and 19 NGCD cases. PLINK (a tool set for whole-genome association and population-based linkage analyses) analysis was used to identify single nucleotide polymorphisms (SNPs) differentiating between groups, and subgroup allele frequencies were also compared to a public genomic database (gnomAD). The Combined Annotation Dependent Depletion scoring tool was used to predict deleteriousness of SNPs. Human leukocyte antigen (HLA) haplotype findings were compared to a control group (n = 8496). PLINK-based analysis between GCD and NGCD groups did not find consistently significant hits. gnomAD control comparisons, however, showed consistent subgroup associations with DGKZ , ESRRA , and GXYLT1 , genes that have been implicated in mammalian granulomatous inflammation. Our findings may guide future research and precision medicine.

The Association Between Lung Cancer and Sarcoidosis: A Literature Review

Lung cancer is responsible for a significant number of cancer-related deaths worldwide. While various factors can lead to lung cancer, such as tobacco smoking, this article focuses on the relationship between sarcoidosis, a multisystem granulomatous disorder, and lung neoplasm. To investigate this association, the authors conducted a literature search using relevant keywords. The analysis of these reports concluded that while Sarcoidosis and lung cancer together is rare, it is possible. The presenting symptoms, age, gender, and diagnostic procedures of each case should be evaluated, and appropriate diagnostic procedures should be carried out to determine the appropriate treatment for each patient. Clinicians need to be aware of the possibility of these two diseases co-occurring, as they can impact the management of the patient's condition, whether it is curative or palliative. It is essential to rule out metastatic cancer in individuals with sarcoidosis-like clinical and radiographic features.