Atypical Skeletal Involvement in Patients with Erdheim-Chester Disease: CT Imaging Findings

ObjectivesTo review retrospectively atypical bone findings from computed tomographic (CT) imaging in patients with Erdheim-Chester disease.MethodsAll 28 patients with Erdheim-Chester disease (13 men and 15 women; mean age, 45 years; range, 7–63 years) underwent chest-abdomen-pelvis CT. CT images were reviewed and analyzed for the various features of atypical bone lesions by two radiologists in consensus. ResultsTwenty-one patients had atypical bone involvement. Radiologically, these atypical osseous lesions were categorized into three types: diffuse, nodular and patchy. Eleven (52%) of the 21 patients had spinal lesions, of which four (36%) had the diffuse type, eight (73%) had the nodular pattern, and six (55%) had the patchy pattern. Sixteen (76%) of the 21 patients had pelvic involvement, of which two (13%) were diffuse, nine (56%) were nodular and 11 were (69%) patchy. Ribs were involved in seven (33%) of the 21 patients, with the nodular pattern in one (14%) patient and the patchy type in six (86%) patients. Clavicle involvement was seen in nine (43%) of the 21 patients, of which the diffuse type was found in only one (11%) patient, the nodular type in six (67%) patients, the solitary patchy type in four (44%) patients. Sternum involvement was seen in 10 (48%) of the 21 patients and all were nodular.ConclusionsThis series provides a detailed description of atypical bone involvement in Erdheim-Chester disease which on CT displays three major patterns. Understanding these patterns may help increase the accuracy of diagnosis of this disease.

Chronic interstitial pneumonia with features of organizing pneumonia in an adult horse

A 22-y-old American Quarter Horse gelding was presented with a history of chronic progressive respiratory problems and a diffuse pulmonary nodular pattern in thoracic radiographs. The horse was euthanized, and 4 formalin-fixed samples of lung were submitted for histopathology. There were multifocal areas of marked thickening of alveolar septa as a result of proliferation of myofibroblasts embedded in fibromyxoid matrix (interpreted as “Masson bodies”), focal areas of fibrosis, and numerous papillary projections of connective tissue into bronchioles. A diagnosis of organizing pneumonia was reached. No etiology was found for this lesion. It is important to consider causes of chronic interstitial pneumonia with fibrosis in horses other than equid herpesvirus 5, such as complicated viral or bacterial pneumonia or chronic toxicoses.

FRI0222 MAGNETIC RESONANCE IMAGING OF MUSCLE INVOLVEMENT IN POLYARTERITIS NODOSA

Background:muscle involvement is frequently reported in polyarteritis nodosa (PAN), mostly as myalgia, muscle swelling, and gait difficulty due to intramuscular arteries involvement, peripheral neuropathy, or myositis with slightly or no elevation of muscle enzymes. Magnetic resonance imaging (MRI) findings of compromised muscles have been reported in isolated cases, mainly as a limited form of PAN, however, muscular involvement patterns in MRI of patients with PAN have been recently describedObjectives:to describe MRI of legs findings in patients with PAN in a tertiary center from Medellin-Colombia.Methods:it was performed a retrospective cross-sectional descriptive study of 15 adult patients who were clinically assessed as having PAN and who had undergone MRI of legs between January 2011 and December 2019. Characteristics already informed in previous studies, affected structures (muscle, subcutaneous tissue, and bone) and pattern of hyperintensities were described as diffuse pattern (signal alterations affecting the entire area of the involved muscle), patched pattern (areas of hyperintensities alternating areas of normal muscle signal intensity), and fluffy nodular pattern or cotton-wool appearance (round hyperintense lesions with fluffy margins centered on blood vessels).Results:clinical characteristics:myalgia, especially calf pain, was the most frequent muscular complaint; other clinical manifestations were: constitutional symptoms (80%), arthralgias or arthritis (50%), mono/polyneuropathy (33%), subcutaneous nodules (33%), livedo reticularis (20%), lower limbs ulcers (13%), abdominal symptoms (13%), and purpura (7%).MRI findings:bilateral muscular edema was found in all patients (100%), fatty infiltration (20%), edema of the subcutaneous cellular tissue (20%), and muscular atrophy (13%) were also described. A diffuse pattern occurred in 46% (n=7) of patients (figure panel A), a patched pattern (figure panel B) in 46% (n=7), and a fluffy nodular pattern or cotton-wool appearance (figure panel C) in 6% (n=1). The most frequently affected muscular group was gastrocnemius and soleus (67%), followed by anterior tibialis (27%), plantar, long peroneus, first finger flexors, and long flexors only affected in 7%. Bone involvement was found in 53%, being the tibia the most affected, followed by the fibula and the calcaneus. MRI led to guide the site of muscle biopsy to prove histological medium-size vasculitis in half of the patients.Conclusion:in patients with PAN suspicion who have muscular complaints, especially calf pain, MRI arises as an important diagnostic tool, and also as a guide to muscular biopsy to prove vasculitis. The patterns associated with PAN are diffuse, patched or fluffy nodular hyperintensities in gastrocnemius and soleus with or without bone compromise.References:[1]Kang, Y. et al. Muscle involvement in polyarteritis nodosa: Report of eight cases with characteristic contrast enhancement pattern on MRI. Am. J. Roentgenol. 206, 378–384 (2016).[2]Hofman DM, Lems WF, Witkamp TD, Putte VD, Bijlsma JW. Demonstration of calf abnormalities by magnetic resonance imaging in polyarteritis nodosa. Clin Rheumatol 1992; 11:402–404.FigureDisclosure of Interests:None declared

Features of radiological and physiological findings in pulmonary capillary hemangiomatosis: an updated pooled analysis of confirmed diagnostic cases

Pulmonary capillary hemangiomatosis (PCH) is a very rare and refractory disease characterized by capillary angioproliferation. The updated classification of pulmonary hypertension categorizes PCH into a subgroup of pulmonary arterial hypertension (PAH) alongside pulmonary veno-occlusive disease (PVOD). However, the definitive diagnosis of PCH only with noninvasive tools remains difficult. The aim of this study was to elucidate the radiological and physiological characteristics of PCH. We searched for cases of pathologically confirmed PCH in the English literature published between 2000 and 2018. We identified 26 cases among 39 studies. Then, we extracted and evaluated the relevant clinical information in all cases with available data. On chest computed tomography (CT), ground-glass opacities (GGOs) were observed in 92% of the cases, in which poorly defined nodular pattern was the most common (88%). GGOs in a bat-wing distribution were observed in one case. Septal lines and lymph node enlargement were observed less frequently (each 19%, 12%). Seven cases (27%) had overlapping abnormalities. Diffusing capacity of the lung for carbon monoxide (DLCO) was remarkably decreased. Alveolar hemorrhage by histological findings or bronchoalveolar lavage (BAL) was observed in seven cases. The present study showed that the most characteristic findings of CT in PCH was centrilobular GGOs with a poorly defined nodular pattern, and septal lines and lymph node enlargement were seen less frequently. Alveolar hemorrhage detected by BAL and decreased DLCO may also be helpful to recognize the possibility of PCH like PVOD.

Spectrum of HRCT findings in interstitial lung diseases and their correlation with mediastinal lymphadenopathy

Background: Interstitial lung disease (ILD) represents a heterogeneous non-infectious group of acute and chronic diseases affecting the lung parenchyma. ILDs are usually associated with significant morbidity and mortality, particularly when fibrosis occurs. ILD is usually associated with mediastinal lymph node enlargement, the extent of lymph node enlargement may correlate to disease activity or progression of fibrosis. In the present study, authors have correlated the spectrum of high-resolution CT findings in ILDs with mediastinal lymph node enlargements.Methods: One hundred and four cases of ILDs confirmed by HRCT findings and pulmonary function tests were included in this study. HRCT was performed using a GE 128 SLICE CT OPTIMA 660 scanner, USA with 1.5 mm collimation at full inspiration. The findings were classified into three groups-fibrotic, ground glassing and nodular pattern. Authors assessed the presence, number and sites of enlarged lymph nodes (short axis ≥10 mm in diameter).Results: The largest subsets of patients were found in the 51-60 age groups. Fibrotic pattern was the most common pattern in this study (50%) followed by ground glassing (44%). Nodular pattern was the least predominant pattern (6%). Lymphadenopathy was seen in 84% of UIP and 63% cases of NSIP. P value was 0.049 which indicates a significant relation between lymphadenopathy and various ILDs. A strong relationship between lymphadenopathy and the predominant fibrotic pattern followed by ground glassing was observed.Conclusions: A significant association was established between lymphadenopathy and the type of ILD where fibrotic pattern had the maximum association.

Surveillance Program for Diagnosis of HCC in Liver Cirrhosis: Role of Ultrasound Echo Patterns

International guidelines suggest ultrasound surveillance for hepatocellular carcinoma (HCC) early diagnosis in liver cirrhosis (LC) patients, but 40% of nodules <2 cm escape detection. We investigated the existence of an ultrasound pattern indicating a higher risk of developing HCC in patients under surveillance. 359 patients with LC (Child-Pugh A-B8) underwent ultrasound screening (median follow-up 54 months, range 12–90 months), liver function tests, alpha-fetoprotein assay, and portal hypertension evaluation. Echo patterns were homogeneous, bright liver, coarse, coarse small nodular pattern, and coarse large nodular pattern. During follow-up 13.9% developed HCC. At multivariate analysis using Cox’s model alpha-fetoprotein, coarse large nodular pattern, portal hypertension, and age were independent predictors of HCC development. Kaplan-Meier estimates of HCC cumulative risk in relation to the baseline echo patterns showed risk of 75% in coarse large nodular pattern patients, 23% coarse small nodular pattern, 21% coarse pattern, 0% homogeneous, and bright liver echo patterns (log-rank test = 23.6, P<0.001). Coarse large nodular pattern indicates a major risk factor for HCC as 40.7% of patients with this pattern developed HCC. Homogeneous and bright liver echo patterns and the absence of portal hypertension were not related to HCC. This observation could raise the question of possibly modifying the follow-up timing in this subset of patients.