Sarcoidosis is a systemic disorder characterized by noncaseating granuloma formation, which can affect any organ in the body; however, skeletal involvement is relatively uncommon. This case report presents a rare case of sarcoidosis primarily affecting the skeletal system in a 39-year-old man with a history of neurosarcoidosis. The patient presented with symptoms of nausea, vomiting, fatigue, weight loss, and lower back and pelvic pain, which were initially suspicious for malignancy. Computed tomography scans revealed lytic bone lesions and lymphadenopathy. However, a biopsy of a left inguinal lymph node confirmed necrotizing granulomatous lymphadenitis, which was consistent with necrotizing sarcoid granulomatosis - a rare variant of sarcoidosis. The patient was treated with systemic corticosteroids, which led to clinical improvement. The prognosis of sarcoidosis is generally good, with spontaneous remission occurring in up to two-thirds of patients; however, some patients may develop chronic and/or progressive disease. In particular, patients with a history of neurosarcoidosis may be at an increased risk for chronic or recurrent disease. This case highlights the importance of considering sarcoidosis in the differential diagnosis of patients presenting with nonspecific symptoms and lymphadenopathy, even in the absence of pulmonary involvement.

Sarcoidosis is a multisystem granulomatous disease of unknown origin. The most frequent localizations are thoracic lymph nodes and/or parenchymal lung disease, nevertheless any other organ may be involved. Musculoskeletal sarcoidosis, previously considered a rare manifestation of the disease, is presently recognized with increasing frequency, due to the development of modern imaging modalities. The classical X-ray sign of bone sarcoidosis is the image of lace in the phalanges of the hands. Most other locations present with atypical radiological images. Therefore, they may mimic metastatic neoplastic disease, especially when they are the first sign of sarcoidosis not previously recognized. On such occasions, none of the imaging methods will give the correct diagnosis, histopathological verification, monitoring of lesions or clinical data in a patient with confirmed sarcoidosis are indicated. The article summarizes the current status of knowledge concerning the recognition and therapy of bone sarcoidosis. In addition, an illustrative case of patient with bone and bone marrow sarcoidosis is presented.

Sarcoidosis, a systemic inflammatory disease of unknown etiology, can affect any site in the body. A bone lesion was unexpectedly detected by fluorodeoxyglucose position emission tomography/computed tomography (FDG PET/CT) in a patient with multiorgan sarcoidosis. FDG PET/CT should be considered for the detection of clinically silent lesions of sarcoidosis.

Bone location is uncommon in both sarcoidosis and in neck cancer (HNC). Diagnosis of a bone lesion is therefore challenging to distinguish its nature in a patient suffering from both diseases. We report the case of a 69-years-old woman referred for P16 positive HPV-HNC. Magnetic Resonance Imaging (MRI) showed T2 hypo-signal on iliac crest and spine. 18FDG-PET demonstrated radiotracer uptake on these locations suggesting bone metastasis. However, bone biopsy showed epithelioid granuloma without malignant cells compatible with sarcoidosis location. The diagnosis of both localized advanced HPV-HNC and systemic sarcoidosis (bone, central nervous system) were retained. The patient received corticosteroid regimen at 0.5mg/kg/day and Methotrexate for sarcoidosis and radiation and chemotherapy with platins for carcinoma. As granulomatous bone marrow infiltration may have an uptake on 18FDG-PET, bone sarcoidosis can mimic metastatic disease. In addition, MRI often fails to distinguish sarcoidosis lesions from metastatic lesion in bones. As no reliable imaging test can decipher both diseases, the description of our case reinforces the necessity to perform bone biopsy in a patient suffering from both conditions to expertise the nature of bone lesions.

Sarcoidosis is a systemic granulomatous inflammatory disease that can involve almost any organ system in the human body. It most frequently presents with pulmonary infiltrates, hilar lymphadenopathy, and skin lesions. Clinical and subclinical involvement of other organ systems is not uncommon. However, the simultaneous development of clinically apparent multisystem sarcoidosis is very rare.
This 44-year-old Caucasian man presented to an outpatient clinic with a 2-month history of fatigue, night sweats, weight loss, loss of appetite, and mild abdominal discomfort. Initial laboratory finding showed elevated liver enzymes. Imaging studies revealed cirrhotic liver with steatosis, few enhancing hepatic masses, and multiple enlarged periaortic and portocaval lymph nodes. Liver biopsy revealed scattered necrotizing granulomatous hepatitis. Positron emission tomography scan showed extensive hepatic uptake, diffuse lymphadenopathy, as well as numerous fluorodeoxyglucose-avid osseous lesions. After extensive workup to rule out malignancy and infectious etiologies, a diagnosis of diffuse multi-organ sarcoidosis was made. He was ultimately treated with methotrexate and steroids, resulting in marked improvement in symptoms and liver function, with stable disease on repeat imaging.
Diffuse multi-organ sarcoidosis is often associated with widespread lymphadenopathy and osseous lesions, which appear indistinguishable from malignancy on imaging. The angiotensin converting enzyme levels and inflammatory markers may be normal. Clinicians should be aware of the possibility of diffuse systemic sarcoidosis in any patient with a remote sarcoidosis history and the simultaneous development of multi-organ-related symptoms.

OBJECTIVE: Spinal sarcoidosis, referring to involvement of the spine in sarcoidosis, is relatively rare and may mimic other neurological disease affecting the spine. The authors present a clinic radiological review of 18 spinal sarcoidosis patients who presented to a tertiary hospital, with emphasis on initial imaging and radiological response to treatment.
METHODS: We retrospectively reviewed our departmental imaging archives over a 15-year period and found 49 cases of neurosarcoidosis out of which 18 patients had spinal magnetic resonance imaging.
RESULTS: Approximately 72% (13/18) of the neurosarcoidosis patients showed some form of spinal involvement. The clinical, epidemiological and imaging data were reviewed for these 13 patients at presentation and follow-up. The findings on magnetic resonance imaging included leptomeningeal enhancement (61%), pachymeningeal (23%), intramedullary enhancing lesions (38%) and bony involvement (15%). The cervical segment was most frequently involved followed by the thoracic segment. Involvement was often long segment (4.2 spinal segments) with proclivity for the dorsal cord. Mean follow-up was 23.2 months. A complete or near-complete radiological response occurred in 66% while partial response was seen in 25% patients. Four patients had isolated central nervous system involvement including one with isolated spinal cord involvement. On diffusion-weighted imaging, the apparent diffusion coefficient of intramedullary lesions was increased compared to normal-appearing cord on baseline and subsequent follow-up scans.
CONCLUSIONS: Spinal sarcoidosis was previously considered uncommon but is being increasingly recognized with widespread use of magnetic resonance imaging. Proclivity for dorsal surface involvement is characteristic, although not necessarily pathognomonic. Also, quantitative diffusion studies may serve as a biomarker for the disease activity and parenchymal injury.

To assess the clinical features, diagnosis, and treatment of bone sarcoidosis in the United States.
Patients with bone sarcoidosis were identified and matched to sarcoidosis patients based on race, gender, and age. Detailed characteristics were obtained by medical record review.
A total of 64 patients with bone sarcoidosis were enrolled in this study. The female:male ratio was 1.46:1 and the white:black ratio was 3:1. Thirty-eight (59.4%) of 64 patients had bone symptoms. Compared to matched cases, bone sarcoidosis patients have more multi-organ involvement and higher incidence with liver, spleen, and extrathoracic lymph node involvement than controls (P < 0.05). Spine was the most commonly affected bone in 44 (68.8%) of patients, followed by pelvis (35.9%), and hands (15.6%). MRI and PET/CT scan was the common imaging technology, which performed in 36 patients and 32 patients, respectively, and with 97.2% and 93.8% positive bone uptake. Laboratory test indicated anemia was more common in bone sarcoidosis group than controls (P = 0.044). Infliximab was more commonly used in bone sarcoidosis patients than controls (P = 0.009).
Bone sarcoidosis was associated with multi-organs affection, and high frequency of liver, spleen, or extrathoracic lymph node involvement. Infliximab should be considered in those patients with aggressive and refractory bone sarcoidosis.