Atypical radiological manifestations of thoracic sarcoidosis: A review and pictorial essay

Sarcoidosis in Johannesburg, South Africa: A retrospective study

Background

Sarcoidosis is a multisystem granulomatous condition of uncertain aetiology that most frequently affects the lungs. Because of clinical and radiological similarities with tuberculosis (TB), particularly in high-prevalence regions, sarcoidosis is frequently misdiagnosed as TB.

Objectives

To review the clinical features of sarcoidosis patients in a South African (SA) population, adding clinical information to the relatively few studies that have been conducted in SA patients with sarcoidosis.

Methods

This was a retrospective study of 102 sarcoidosis patients conducted between 2002 and 2006 at the Charlotte Maxeke Johannesburg Academic Hospital.

Results

Of 102 sarcoidosis patients, there were 69 (67.6%) females and 33 (32.4%) males. The majority (85.3%) were non-smokers. The mean age of the group was 44.6 years. One-third of patients had chronic comorbid diseases. Almost 17% had been treated initially for TB, prior to being diagnosed as having sarcoidosis. Two patients developed active TB while receiving corticosteroid treatment for sarcoidosis. The salient clinical manifestations were dry cough (the most common presenting symptom in 82.4%), dyspnoea in 53.9%, cutaneous lesions other than erythema nodosum in 33.3%, and on lung examination crackles were noted in 37.3% of patients. Raised angiotensin-converting enzyme (ACE) levels were found in 56.8% of patients. The majority (48%) of patients had stage II chest radiographic changes. Cutaneous (28.4%), mediastinal lymph node (25.5%) and transbronchial lung (25.5%) biopsies were the most frequent sites confirming granulomatous inflammation. Overall, 21.2% of patients had obstructive airway disease. Systemic corticosteroids were indicated in 87.3% of patients and the relapse rate was 60.7%.

Conclusion

Sarcoidosis is often initially misdiagnosed as TB in SA. The most common biopsy sites for histological confirmation were the skin and mediastinal lymph nodes, and transbronchial lung biopsies were also frequently taken. Stage II chest radiographic changes were most common. Overall, systemic corticosteroids were administered in 87.3% of cases and the relapse rate was 60.7%.

Challenging Mimickers in the Diagnosis of Sarcoidosis: A Case Study

Sarcoidosis is a systemic granulomatous disease of unknown cause characterized by a wide variety of presentations. Its diagnosis is based on three major criteria: a clinical presentation compatible with sarcoidosis, the presence of non-necrotizing granulomatous inflammation in one or more tissue samples, and the exclusion of alternative causes of granulomatous disease. Many conditions may mimic a sarcoid-like granulomatous reaction. These conditions include infections, neoplasms, immunodeficiencies, and drug-induced diseases. Moreover, patients with sarcoidosis are at risk of developing opportunistic infections or lymphoma. Reliably confirming the diagnosis of sarcoidosis and better identifying new events are major clinical problems in daily practice. To address such issues, we present seven emblematic cases, seen in our department, over a ten-year period along with a literature review about case reports of conditions misdiagnosed as sarcoidosis.

Comparison of typical and atypical computed tomography patterns regarding reversibility and fibrosis in pulmonary sarcoidosis

PURPOSE:

This study aims to investigate whether there is a significant difference between typical and atypical parenchymal patterns in the development of fibrosis, which is the most crucial factor affecting morbidity in pulmonary sarcoidosis.

METHODS:

In our hospital, 145 cases with Siltzbach Types 2 and 3 sarcoidoses diagnosed by clinical, radiological, and histopathologic were retrospectively investigated. Perilymphatic nodules, accompanying mosaic attenuation, and interlobular septal thickening and central peribronchovascular bunch-like thickening on high-resolution computed tomography were assessed as typical. Solid nodules, galaxy finding, consolidation, ground-glass opacity, isolated mosaic attenuation, and interlobular septal thickening, and pleural fluid were accepted as atypical findings. Findings indicating fibrosis were fine and rough reticular opacity, traction bronchiectasis, volume loss, and cystic changes. For the analysis of variables, SPSS 25.0 program was used.

RESULTS:

Ten (16%) of the 61 cases with typical findings and 16 (19%) of the 84 with atypical findings developed fibrosis (P = 0.827). The mean age of cases with fibrosis was higher. With the cut-off of 50 years, sensitivity was 61.5%, and specificity was 68.9%. The highest fibrosis rate was in cases with ground glass pattern (n = 7/17), whereas higher reversibility rates were in those with miliary pattern (n = 9/12) and galaxy sign (n = 5/6).

CONCLUSION:

The incidence of fibrosis is higher in the atypical group with no significant difference. The incidence of fibrosis differs in each atypical pattern, being highest in ground-glass opacity and lowest in the miliary pattern.

A Rare Case Study About Necrotizing Granulomatous Sarcoidosis

Sarcoidosis is a granulomatous disorder with an elusive etiology and pathogenesis. Classically, sarcoidosis is associated with non-caseating granulomas composed of mononuclear phagocytes, lymphocytes, and multinucleated giant cells. Necrotizing granulomas can also be associated with sarcoidosis but is scarcely reported in the medical literature. Necrotizing sarcoid granulomatosis is challenging to diagnose due to its rarity and similarity with other necrotizing disorders. Therefore, it is mainly considered a diagnosis of exclusion. We report one such case study, which could prompt further research to lay the course of treatment strategies for this disease. Moreover, our patient had a family history of sarcoidosis, which raises questions regarding possible genetic predisposition, and future work might help solve this medical mystery.

Ultrasonographic evaluation of lung parenchyma involvement in sarcoidosis

PURPOSE

To use ultrasonography (USG) for the evaluation of lung parenchyma in patients with sarcoidosis, andto compare the USG findings with the results of a high-resolution computerized tomography (HRCT) and pulmonary function test-carbon monoxide diffusion test (PFT-DLCO), which are commonly used methods in the evaluation of parenchymal involvement in sarcoidosis.

MATERIAL AND METHODS

Patients with sarcoidosis and healthy controls were enrolled in the study between January 2015 and December 2017. The clinical findings, HRCT and PFT-DLCO results of all subjects were recorded, and USG findings and comet tail artifact (CTA) measurements were recorded by another pulmonologist. The USG, HRCT and SFT-DLCO findings were compared between the two groups. Based on the findings of theclinical-radiologic investigations and PFT-DLCO, as the current gold standard in diagnosis, the sensitivity and specificity of USG in demonstrating lung parenchyma involvement in sarcoidosis patients were estimated.

FINDINGS

The sarcoidosis group consisted of 79 patients and the control group included 34 subjects. The mean number of CTAs in the sarcoidosis and control groups was 33.4 and 25, respectively (p=0.001). In the sarcoidosis group, the number of CTAs in patients with DLCO% <80 and ≥80% was 37.4 and 29.7, respectively (p=0.011), and a negative correlation was identified between the number of CTAs and DLCO% (p=0.019 r=-0.267). The mean number of CTAs in patients with and without parenchymal involvement in HRCT was 36 and 25.5, respectively (p=0.001). The number of CTAs in the patients with sarcoidosis with a normal DLCO% value (≥80%) was higher than in the control group (p=0.014). The diagnostic sensitivity and specificity of thoracic USG were found to be 76% and 53%, respectively.

CONCLUSION

The number of CTAs in patients with sarcoidosis was higher than that of the healthy controls. The number of CTAs in patients with sarcoidosis with parenchymal involvement in HRCT and/or a low DLCO (<80%) was also elevated. Thoracic USG has a high sensitivity (76%) in demonstrating parenchymal involvement in patients with sarcoidosis.

Hypercalcemia-induced acute kidney injury in a Caucasian female due to radiographically silent systemic sarcoidosis

Abstract. Sarcoidosis is a rare autoimmune disease resulting in formation of non-necrotizing “non-caseating” granulomas generally in the lung. The disease classically strikes African American females in their fourth and fifth decades. The resulting hypercalcemia is a result of 1-α hydroxylase overexpression in granulomas with increased 1,25-dihydroxy vitamin D levels. This phenomenon can also be observed in mycobacterial and fungal infections that produce granulomas in infected patients. Thus, chronic infectious diseases are part of differential diagnosis of granulomatous processes. We present an elderly Caucasian female who presented with hypercalcemia with serum calcium of 11 – 14 mg/dL and an elevated ionized calcium of 1.4 – 1.5 mmol/L. Initially cholecalciferol supplements were stopped, but hypercalcemia persisted for more than 2 months. 1,25-dihydroxy vitamin D levels were markedly elevated with low normal 25-hydroxy vitamin D levels, angiotensin-converting enzyme levels were also high, and chest computed tomography (CT) imaging was negative for any lymphadenopathy (including perihilar lymphadenopathy). Malignancy and infectious workups were negative for fungal and mycobacterial infections. Positron emission tomography revealed several small lymph nodes in right upper lobe of lung, and biopsy of bone marrow and lung lymph-nodes revealed non-caseating granulomata. We present an atypical case of occult sarcoidosis presenting mainly with biochemical findings without any definitive imaging findings, making diagnosis a clinical challenge.

Thoracic Sarcoidosis: Imaging with High Resolution Computed Tomography

INTRODUCTION

Sarcoidosis is a disease of unknown aetiology that primarily affects the lungs. Clinical and radiological findings with demonstration of non caseating granulomas on pathology is utilised for diagnosing the disease.

AIM

To assess and evaluate the features of thoracic sarcoidosis on High Resolution Computed Tomography (HRCT) chest.

MATERIALS AND METHODS

A total of 40 (31 males and 9 females) cases of pulmonary sarcoidosis in a period of three years were included in this study. Patients underwent detailed clinical evaluation, imaging, Pulmonary Function Tests (PFT) and pathological confirmation of disease. Chest radiograph was obtained in all patients. HRCT was done on 16 slice Computed Tomography (CT) using 1 mm slice thickness and high spatial frequency algorithm for image re-construction. Images were viewed and evaluated using appropriate lung and mediastinal windows. The lymph nodes were classified as hilar and mediastinal with Maximum Short Axis Diameter (MSAD) more than 10 mm taken as cut-off for enlargement. Pulmonary opacities were classified as nodules (micronodules 1-4 mm and macronodules >5 mm), reticular opacities, fibrotic lesions, ground glass opacities and consolidations. Nodule distribution classified as perilymphatic centrilobular and random. Repeat scanning done on follow up or as clinically indicated.

RESULTS

A total of five patients had Stage I disease, 24 patients had Stage II disease, eight patients had Stage III disease and three patients had stage IV disease. Mediastinal lymphdenopathy present in 29 patients. Bilateral hilar adenopathy was the predominant pattern seen in 22 patients. Lung parenchymal lesions excluding end stage disease noted in 32 patients. The characteristic HRCT lung parenchymal involvement of micronodules with a perilymphatic distribution was seen in 26 patients. HRCT features of predominant upper and middle lobe distribution seen in majority of patients. Documented atypical lesions and the characteristic features of end stage lung disease on HRCT noted in a small subset of patients. HRCT was superior to chest radiography for evaluating the features, pattern and distribution of the parenchymal lesions and mediastinal lymph nodes, for assessing the stage and activity of the disease and in aiding detection of subtle parenchymal lesions which are liable to be missed on conventional imaging.

CONCLUSION

Thoracic sarcoidosis can have varied presentations. HRCT is superior to conventional CT for the detection and characterisation of the lung parenchymal lesions.

Thoracic lymphadenopathy in benign diseases: A state of the art review

Lymphadenopathy is a common radiological finding in many thoracic diseases and may be caused by a variety of infectious, inflammatory, and neoplastic conditions. This review aims to describe the patterns of mediastinal and hilar lymphadenopathy found in benign diseases in immunocompetent patients. Computed tomography is the method of choice for the evaluation of lymphadenopathy, as it is able to demonstrate increased size of individual nodes, abnormalities of the interface between the mediastinum and lung, invasion of surrounding fat, coalescence of adjacent nodes, obliteration of the mediastinal fat, and hypo- and hyperdensity in lymph nodes. Intravenous contrast enhancement may be needed to help distinguish nodes from vessels. The most frequent infections resulting in this finding are tuberculosis and fungal disease (particularly histoplasmosis and coccidioidomycosis). Sarcoidosis is a relatively frequent cause of lymphadenopathy in young adults, and can be distinguished from other diseases - especially when enlarged lymph nodes are found to be multiple and symmetrical. Other conditions discussed in this review are silicosis, drug reactions, amyloidosis, heart failure, Castleman's disease, viral infections, and chronic obstructive pulmonary disease.

Sarcoid lung

Sarcoidosis is a multisystem disease with a varied clinical presentation. The lung disease is common and is responsible for most of the morbidity and mortality associated with sarcoidosis. Tuberculosis remains a prevalent disease in some countries, such as Portugal. There are reports of sequential occurrence of these identities. The authors present a case of a patient with lymphatic tuberculosis who, some years after treatment of this infection, was diagnosed with sarcoidosis in an atypical pseudotumoural presentation.