Novel dietary protocol prior to 18F-fluorodeoxyglucose positron emission tomography to evaluate for cardiac sarcoidosis.

The diagnosis of cardiac sarcoidosis (CS) is challenging. Recently, guidelines incorporated cardiac positron emission tomography (PET) with 18F-Fluorodeoxyglucose (F18-FDG) as a non-invasive diagnostic modality for the detection and follow-up of CS. However, this technique is dependent of patient dietary preparation to suppress physiological myocardial F18-FDG uptake. We present a case of possible CS which highlights a novel preparation protocol that facilitated appropriate myocardial suppression.

[Disturbances of calcium metabolism and vitamin D supplementation in sarcoidosis - two-way street]. / Zaburzenia gospodarki wapniowej a suplementacja witaminy D u chorych na sarkoidoze ­ dwie strony medalu.

The role of vitamin D in the human body is not limited only to the regulation of calcium metabolism and secondary to the impact on bones. Recent studies have shown the influence of vitamin D level on muscles, on the risk of cancer, diabetes, hypertension and pulmonary diseases, including granulomatous diseases. Sarcoidosis is a granulomatous disease of unknown etiology. Hypercalcemia in the course of the disease occurs in up to 10% of cases in the consequence of autonomous overproduction of 1,25-dihydroxyvitamin D by macrophages of sarcoid granulomas. Hypercalciuria occurs 3-fold more frequent. On the other hand, treatment with corticosteroids increases the risk of osteoporosis. Vitamin D intake is recommended for prevention of osteoporosis. Such management, in sarcoidosis patients, is not so clear because of risk of hypercalcemia. Vitamin D supplementation, according to current recommendations for general population, is based solely on 25-hydroxyvitamin D level testing. This seems to be not safe in the group of sarcoidosis patients. This article discusses the role of vitamin D in sarcoidosis patients and current opinion on vitamin D supplementation in this group.

¹8F-Fluoro-2-deoxyglucose positron emission tomography in cardiac sarcoidosis.

Cardiac sarcoidosis (CS) is a rare and potentially life-threatening disease that causes conduction disturbance, systolic dysfunction, and most notably sudden cardiac death. Accurate diagnosis of CS is thus mandatory; however, a reliable approach that enables diagnosis of CS with high sensitivity and specificity has yet to be established. Recent studies have demonstrated the promising potential of (18)F-fluoro-2-deoxyglucose positron emission tomography ((18)F-FDG PET) in the diagnosis and assessment of CS. Indeed, (18)F-FDG PET provides a wide variety of advantages over previous imaging modalities; however, there are pitfalls and limitations that should be recognized. In this review article, (1) the rationale for (18)F-FDG PET application in CS, (2) suitable pretest preparations, and (3) evaluation protocols for the (18)F-FDG PET images obtained will be addressed. In particular, sufficient suppression of physiological (18)F-FDG uptake in the heart is essential for accurate assessment of CS. Also, (4) recent studies addressing the diagnostic role of (18)F-FDG PET and (5) the clinically important differences between (18)F-FDG PET and other imaging technologies will be reviewed. For example, active sarcoid lesions and their response to steroid treatment will be better detected by (18)F-FDG PET, whereas fibrotic lesions might be shown more clearly by magnetic resonance imaging or other nuclear myocardial perfusion imaging. In the last decade, (18)F-FDG PET has substantially enhanced detection of CS; however, CS would be better evaluated by a combination of multiple modalities. In the future, advances in (18)F-FDG PET and other emerging imaging modalities are expected to enable better management of patients with sarcoidosis.

Observations on the different calcium metabolic patterns in sarcoidosis. A metabolic and kinetic study.

Combined calcium balance and 47Ca turnover studies in sarcoidosis (4 patients) and vitamin D intoxication (1 patient) disclosed three different patterns of calcium metabolism. On patient with sarcoidosis had a normal metabolism of calcium, and two patients presented the usual pattern of intestinal hyperabsorption, hypercalcemia, and hypercalciuria. The fourth patient with sarcoidosis and the patient with vitamin D intoxication, both studied during spontaneous remissions, presented the third pattern. The main features here were hypercalcemia despite normal intestinal absorption of calcium, enlarged exchangeable calcium pool, accelerated accretion and resorption rates, hypercalciuria, and a distinctly negative calcium balance. This pattern of remission seems to represent a mobilization of extraosseous or metastatic calcifications, rather than a resorption of bone calcium.