From Head to Toe: Granulomatosis with Polyangiitis

Noninfectious Granulomatous Lung Disease: Radiological Findings and Differential Diagnosis

Granulomatous lung diseases (GLDs) are a heterogeneous group of pathological entities that can have different clinical presentations and outcomes. Granulomas are histologically defined as focal aggregations of activated macrophages, Langerhans cells, and lymphocytes, and may form in the lungs when the immune system cannot eliminate a foreign antigen and attempts to barricade it. The diagnosis includes clinical evaluation, laboratory testing, and radiological imaging, which especially consists of high-resolution computed tomography. bronchoalveolar lavage, transbronchial needle aspiration or cryobiopsy, positron emission tomography, while genetic evaluation can improve the diagnostic accuracy. Differential diagnosis is challenging due to the numerous different imaging appearances with which GLDs may manifest. Indeed, GLDs include both infectious and noninfectious, and necrotizing and non-necrotizing granulomatous diseases and the imaging appearance of some GLDs may mimic malignancy, leading to confirmatory biopsy. The purposes of our review are to report the different noninfectious granulomatous entities and to show their various imaging features to help radiologists recognize them properly and make an accurate differential diagnosis.

The visualization of hypertrophic pachymeningitis in antineutrophil cytoplasmic antibody-associated granulomatosis with polyangiitis on contrast-enhanced FLAIR

Hypertrophic pachymeningitis is a rare inflammatory condition that leads to the thickening of the dura mater, either due to unknown or identifiable secondary causes. Granulomatosis with polyangiitis is a notable causative agent, and hypertrophic pachymeningitis is the initial presentation in certain cases. The diagnosis of hypertrophic pachymeningitis is aided by contrast-enhanced MRI, although distinguishing between normal and abnormal dural enhancement can be challenging using contrast-enhanced T1WI. This study highlights the case of an 80-year-old woman diagnosed with hypertrophic pachymeningitis secondary to antineutrophil cytoplasmic antibody-associated granulomatosis with polyangiitis, where contrast-enhanced FLAIR played a crucial role in distinctly identifying abnormal dural enhancement and differentiating it from normal dura. In conclusion, although contrast-enhanced T1WI remains indispensable, contrast-enhanced FLAIR can serve as a valuable complementary tool in MRI study sequences for the diagnosis of hypertrophic pachymeningitis.

Tuberculous Meningitis or Neurosarcoidosis-a Diagnostic Quandary. From the National Multiple Sclerosis Society Case Conference Proceedings

Distinguishing granulomatous diseases remains diagnostically challenging. Clinical phenotypes and neuroimaging findings resemble many infectious and noninfectious disorders. We describe a Hispanic/Latino man diagnosed with tuberculous meningitis who deteriorated neurologically after treatments. Additional workup revealed a pathology more consistent with neurosarcoidosis. Care access delays and social circumstances likely complicated his diagnosis.

Immune-Mediated Hypertrophic Pachymeningitis and its Mimickers: Magnetic Resonance Imaging Findings

Hypertrophic pachymeningitis (HP) is a rare and chronic inflammatory disorder presenting as localized or diffuse thickening of the dura mater. It can be idiopathic or an unusual manifestation of immune-mediated, infectious, and neoplastic conditions. Although some cases may remain asymptomatic, HP can lead to progressive headaches, cranial nerve palsies, hydrocephalus, and other neurological complications, which makes its recognition a fundamental step for prompt treatment. Regarding the diagnosis workup, enhanced MRI is the most useful imaging method to evaluate dural thickening. This article addresses the MR imaging patterns of immune-mediated HP, including immunoglobulin G4-related disease, neurosarcoidosis, granulomatosis with polyangiitis, rheumatoid pachymeningitis, and idiopathic HP. The main infectious and neoplastic mimicking entities are also discussed with reference to conventional and advanced MR sequences.

Infectious and Inflammatory Processes of the Orbits in Children

Most primary orbital pathology in children is due to bacterial infection. Radiologists typically encounter these cases to evaluate for clinically suspected postseptal orbital involvement. Contrast-enhanced cross-sectional imaging is important for the detection and early management of orbital infection and associated subperiosteal/orbital abscess, venous thrombosis, and intracranial spread of infection. Benign mass-like inflammatory processes involving the pediatric orbit are rare, have overlapping imaging features, and must be distinguished from orbital malignancies.

Neuroimaging of hypophysitis: etiologies and imaging mimics

Hypophysitis is an inflammatory disease affecting the pituitary gland. Hypophysitis can be classified into multiple types depending on the mechanisms (primary or secondary), histology (lymphocytic, granulomatous, xanthomatous, plasmacytic/IgG4 related, necrotizing, or mixed), and anatomy (adenohypophysitis, infundibulo-neurohypophysitis, or panhypophysitis). An appropriate diagnosis is vital for managing these potentially life-threatening conditions. However, physiological morphological alterations, remnants, and neoplastic and non-neoplastic lesions may masquerade as hypophysitis, both clinically and radiologically. Neuroimaging, as well as imaging findings of other sites of the body, plays a pivotal role in diagnosis. In this article, we will review the types of hypophysitis and summarize clinical and imaging features of both hypophysitis and its mimickers.

Dural and Leptomeningeal Diseases: Anatomy, Causes, and Neuroimaging Findings

Meningeal lesions can be caused by various conditions and pose diagnostic challenges. The authors review the anatomy of the meninges in the brain and spinal cord to provide a better understanding of the localization and extension of these diseases and summarize the clinical and imaging features of various conditions that cause dural and/or leptomeningeal enhancing lesions. These conditions include infectious meningitis (bacterial, tuberculous, viral, and fungal), autoimmune diseases (vasculitis, connective tissue diseases, autoimmune meningoencephalitis, Vogt-Koyanagi-Harada disease, neuro-Behçet syndrome, Susac syndrome, and sarcoidosis), primary and secondary tumors (meningioma, diffuse leptomeningeal glioneuronal tumor, melanocytic tumors, and lymphoma), tumorlike diseases (histiocytosis and immunoglobulin G4-related diseases), medication-induced diseases (immune-related adverse effects and posterior reversible encephalopathy syndrome), and other conditions (spontaneous intracranial hypotension, amyloidosis, and moyamoya disease). Although meningeal lesions may manifest with nonspecific imaging findings, correct diagnosis is important because the treatment strategy varies among these diseases. ©RSNA, 2023 Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. Quiz questions for this article are available through the Online Learning Center.

Cutaneous Deep Ulcerations as Initial Presentations of Granulomatosis with Polyangiitis: Two Case Reports and Differential Diagnosis

Background: Granulomatosis with polyangiitis (GPA) is an antineutrophil-cytoplasmic-antibody (ANCA)-associated small-vessel vasculitis characterized by necrotizing granulomatous inflammation. Symptoms of skin involvement can appear in 30–50% of patients with GPA, and may present as the initial presentation. Case Presentation: We describe two patients who presented with multiple deep, large, nonhealing skin ulcers postoperatively with purulent drainage and fever. Both patients were diagnosed with GPA after an extensive evaluation, including histopathology. Infectious, connective tissue disease and malignant etiologies were excluded. Their cANCA and PR3-ANCA levels were positive. Patient 2 was diagnosed early and recovered well after treatment with corticosteroids and rituximab; however, Patient 1 had a poor prognosis due to a long disease course. Conclusions: Diseases with multiple deep, large skin ulcers and fever can be infectious or noninfectious. Atypical manifestations may lead to missed diagnosis and misdiagnosis. GPA may initially present in a localized form before progressing to a generalized disease. The two cases we have highlighted will prompt clinicians to nevertheless call for a low threshold for diagnosis.

The eye is a common site of granulomatosis with polyangiitis. A collaborative study

BACKGROUND

Ocular manifestations of granulomatosis with polyangiitis (GPA) have been reported in a limited number of studies and with largely variable frequency. Here we report on the clinical, diagnostic, and therapeutic features of a cohort of 63 GPA patients, with particular regard to 22 of them with ophthalmic involvement (35%).

METHODS

Clinical manifestations, results of immunological findings, histopathological pictures, imaging data, Birmingham Vasculitis Activity Score, therapeutic regimens, and outcomes were retrospectively analyzed. At diagnosis, in addition to a structured clinical assessment, all patients underwent a comprehensive ophthalmologic examination.

RESULTS

The most frequently involved organs were kidneys, lungs, ear/nose/throat, and eyes. Ocular manifestations were bilateral in 32%. The three most commonly diagnosed ophthalmologic manifestations were scleritis (36%), retro-orbital pseudotumor or orbital mass (23%), and episcleritis (13%). Ocular and systemic involvement were simultaneously present at onset in 41% of the patients; systemic involvement was followed by ocular lesions in 36%; ocular inflammation was followed by systemic manifestations in 18%; and an orbital mass in the absence of systemic disease characterized 5%. Glucocorticoids plus cyclophosphamide and glucocorticoids plus rituximab were the combined therapies most frequently employed during remission induction and remission maintenance, respectively. Persistent ophthalmologic and extra-ocular remissions were achieved in 77 and 64% of the patients, respectively. One to three systemic relapses were diagnosed in 7 patients (31.8%). At the last follow-up, a visual outcome 20/40 or better in 31 (70%) of 44 eyes was determined.

CONCLUSIONS

The eye was involved in over one third of our patients with GPA. Increased awareness, early diagnosis, and multi-specialty collaboration are critical in achieving a favorable outcome of GPA.

Mucormycosis an added burden to Covid-19 Patients: An in-depth systematic review

As of 25th July, 2022, global Disease burden of 575,430,244 confirmed cases and over 6,403,511 deaths have been attributed to coronavirus disease 2019 (COVID-19). Co-infections/secondary infections continue to plague patients around the world as result of the co-morbidities like diabetes mellitus, biochemical changes caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) especially significant elevation in free iron levels, immune suppression caused by SARS-CoV-2, and indiscriminate use of systemic corticosteroids for the treatment of severe COVID-19 disease. In such circumstances, opportunistic fungal infections pose significant challenge for COVID-19 disease therapy in patients with other co-morbidities. Although COVID-19-associated Mucormycosis (CAM) has been widely recognized, currently extensive research is being conducted on mucormycosis. It has been widely agreed that patients undergoing corticosteroid therapy are highly susceptible for CAM, henceforth high index of screening and intensive care and management is need of an hour in order to have favorable outcomes in these patients. Diagnosis in such cases is often delayed and eventually the disease progresses quickly which poses added burden to clinician and increases patient load in critical care units of hospitals. A vast perusal of literature indicated that patients with diabetes mellitus and those with other co-morbidities might be highly vulnerable to develop mucormycosis. In the present work, the case series of three patients presented at Chest Disease Hospital Srinagar, Jammu and Kashmir infected with CAM has been described with their epidemiological data in supplementary section. All these cases were found to be affected with co-morbidity of Diabetes Mellitus (DM) and were under corticosteroid therapy. Furthermore, given the significant death rate linked with mucormycosis and the growing understanding of the diseases significance, systematic review of the literature on CAM has been discussed and we have attempted to discuss emerging CAM and related aspects of the disease.

Granulomatosis with polyangiitis: Common and uncommon presentations

Granulomatosis with polyangiitis (GPA) is a multisystemic autoimmune small vessel vasculitis predominantly affecting the respiratory and renal systems. Other systems such as the central nervous system, orbital, cardiac and gastrointestinal systems may also be involved to a lesser degree. Although there are no imaging features that are pathognomonic for GPA, there are known radiological patterns suggestive of the disease and imaging plays an important role in diagnosis, assessment and monitoring of disease activity. This is more evident when combined with clinical features, biochemical values and histopathology results. This pictorial review aims to present both common and uncommon radiological features of GPA.

Orbital Muscle Enlargement: What if It’s Not Graves’ Disease?

Purpose of Review

To provide the radiologist with tools to recognize findings atypical for Graves’ ophthalmopathy and differentiate between the most important and common alternative causes of extraocular muscle enlargement on CT and MR imaging.

Recent findings

We introduce five ‘red flags’ representing features that are atypical for Graves’ ophthalmopathy: unilateral disease, atypical pattern of muscle involvement, adjacent structure involvement, restricted diffusion, and absence of pain.

Summary

About 95% of the cases with extraocular enlargement are due to Graves’ ophthalmopathy, other causes are less well known and recognized. The ‘red flags’ may aid in recognizing and suggesting alternative diagnoses.