Refractory multisystem sarcoidosis responding to infliximab therapy

Re-evaluating serum angiotensin-converting enzyme in sarcoidosis

Sarcoidosis is a systemic inflammatory disease of unknown etiology, which mainly affects the lungs and lymph nodes, as well as extrapulmonary organs. Its incidence, and prevalence rate, and disease course largely vary with regions and populations globally. The clinical manifestations of sarcoidosis depend on the affected organs and the degree of severity, and the diagnosis is mainly based on serum biomarkers, radiographic, magnetic resonance, or positron emission tomography imaging, and pathological biopsy. Noncaseating granulomas composing T cells, macrophages, epithelioid cells, and giant cells, were observed in a pathological biopsy, which was the characteristic pathological manifestation of sarcoidosis. Angiotensin-converting enzyme (ACE) was first found in the renin-angiotensin-aldosterone system. Its main function is to convert angiotensin I (Ang I) into Ang II, which plays an important role in regulating blood pressure. Also, an ACE insertion/deletion polymorphism exists in the human genome, which is involved in the occurrence and development of many diseases, including hypertension, heart failure, and sarcoidosis. The serum ACE level, most commonly used as a biomarker in diagnosing sarcoidosis, in patients with sarcoidosis increases. because of epithelioid cells and giant cells of sarcoid granuloma expressing ACE. Thus, it serves as the most commonly used biomarker in the diagnosis of sarcoidosis and also aids in analyzing its therapeutic effect and prognosis in patients with sarcoidosis.

Renal sarcoidosis

Renal sarcoidosis (RS) is a rare form of sarcoidosis that results in granulomatous inflammation of renal parenchyma. We describe the epidemiology, pathogenesis, clinical features, diagnostic approach, treatment strategies and outcomes of this condition. RS occurs most commonly at the time of initial presentation of sarcoidosis but can at any time along the course of the disease. The most common presenting clinical manifestations of RS are renal insufficiency or signs of general systemic inflammation. End-stage renal disease requiring dialysis is a rare initial presentation of RS. The diagnosis of RS should be considered in patients who present with renal failure and have either a known diagnosis of sarcoidosis or have extra-renal features consistent with sarcoidosis. A renal biopsy helps to establish the diagnosis of RS, with interstitial non-caseating granulomas confined primarily to the renal cortex being the hallmark pathological finding. However, these histologic findings are not specific for sarcoidosis, and alternative causes for granulomatous inflammation of the renal parenchyma should be excluded. Corticosteroids are the drug of choice for RS. Although RS usually responds well to corticosteroids, the disease may have a chronic course and require long-term immunosuppressive therapy. The risk of progression to ESRD is rare.

In vivo evaluation of TNF-alpha in the lungs of patients affected by sarcoidosis

INTRODUCTION

Sarcoidosis is a multisystemic granulomatous disorder characterized by multiple noncaseating granulomas involving intrathoracic lymph nodes and lung parenchyma. Recently, the use of anti-tumor necrosis factor alpha (anti-TNFα) agents has been introduced for therapy of chronic and refractory sarcoidosis with controversial results. Infliximab (Remicade) is a chimeric monoclonal antibody (mAb) that recognizes and binds TNFα, neutralizing its biological effects. In the present study,   (99m)Tc labelled infliximab was used to study the expression of TNFα in sarcoid lesions and to evaluate its role as a predictive marker in response to therapy with Remicade.

MATERIAL AND METHODS

A total of 10 patients with newly diagnosed sarcoidosis were enrolled together with 10 control patients affected by rheumatoid arthritis. All patients were studied by planar imaging of the chest with   (99m)Tc-infliximab at 6 h and 24 h and total body [(18)F]-FDG PET/CT. Regions of interest were drawn over the lungs and the right arm and target-to-background ratios were analysed for   (99m)Tc-infliximab. SUV mean and SUV max were calculated over lungs for FDG.

RESULTS AND DISCUSSION

Image analysis showed low correlation between T/B ratios and BAL results in patients despite positivity at [(18)F]-FDG PET.

CONCLUSION

In conclusion, patients with newly diagnosed pulmonary sarcoidosis, with FDG-PET and BAL positivity, showed a negative   (99m)Tc-infliximab scintigraphy.

[Kidney involvement in sarcoidosis]

Sarcoidosis is a chronic multisystemic inflammatory disorder of unknown etiology, characterized by the presence of non-necrotizing epithelioid and giant cell granulomas. Various renal manifestations have been reported in patients with sarcoidosis. Disorders of bone and mineral metabolism related to the overexpression of 25-hydroxyvitamin-D1α-hydroxylase by alveolar and granuloma macrophages are frequently associated with sarcoidosis. Hypercalcemia and hypercalciuria are a major cause of renal injury predisposing to pre renal azotemia, acute tubular necrosis, nephrolithiasis and nephrocalcinosis. Therapeutic management of hypercalcemia includes preventive measures (limited sunlight exposure, limited vitamin D and calcium intakes, and adequate hydration) and specific treatment in cases of severe hypercalcemia (corticosteroid therapy, chloroquine or ketoconazole). Granulomatous tubulointerstitial nephritis is the most common renal lesion associated with sarcoidosis leading to end stage renal disease in some patients. In these cases, interstitial fibrosis seems to appear early in the course of sarcoidosis and is a major prognostic factor requiring rapid corticosteroid therapy to reduce the risk of severe renal impairment. Membranous nephropathy seems to be the most frequent glomerular disease that may occur in association with sarcoidosis. Among kidney allograft recipients, the risk of recurrence of granulomatous tubulointerstitial nephritis is high and may have a negative impact on the graft survival.

Paradoxical inflammation induced by anti-TNF agents in patients with IBD

Anti-TNF antibodies have acquired a prominent place in the management of IBD (including Crohn's disease and ulcerative colitis), rheumatologic conditions (such as rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis) and psoriasis. They have a good safety profile, especially when contraindications such as demyelinating disease, active infections and/or abscesses are ruled out, and when necessary precautions to prevent reactivation of tuberculosis are taken. However, with increasing use of these agents, paradoxical adverse events have been reported. Some of these features are shared with the underlying disease for which these drugs are given, making management of these conditions challenging. For example, anti-TNF therapy is used for the treatment of psoriasis, but psoriasiform lesions are sometimes observed in patients receiving therapy. Similarly, anti-TNF therapy is used for the treatment of rheumatologic diseases, but arthralgias and arthritis are sometimes observed in patients receiving anti-TNF agents. We review the paradoxical inflammation induced by anti-TNF agents in patients with IBD, provide hypotheses for the occurrence of this paradoxical inflammation and give practical advice on how to manage these patients.