Impact of small intestinal bacterial overgrowth on systemic inflammation, circulatory and renal function, and liver fibrosis in patients with cirrhosis and ascites.

Background: Small intestinal bacterial overgrowth (SIBO) occurs frequently in patients with cirrhosis, particularly in those with ascites, and promotes the translocation of gut-derived bacterial products into the portal and systemic circulation. We investigated the effects of SIBO on systemic inflammatory activity, circulatory and renal function, and the degree of liver fibrosis in patients with cirrhosis and ascites. Methods: Eighty patients with cirrhosis and ascites were prospectively enrolled. SIBO was determined by lactulose breath test. Serum levels of lipopolysaccharide-binding protein (LBP), tumor necrosis factor-α, and interleukin-6, mean arterial pressure (MAP), cardiac output (CO) by echocardiography, systemic vascular resistance (SVR) as MAP/CO ratio, plasma renin activity (PRA), plasma aldosterone, radioisotope-assessed glomerular filtration rate (GFR), and liver stiffness by shear wave elastography were evaluated. Results: SIBO was detected in 58 patients (72.5%). Compared to patients without SIBO, those diagnosed with SIBO had significantly higher LBP levels (P<0.001), significantly lower MAP (P<0.001) and SVR (P<0.001), and significantly higher CO (P=0.002) and PRA (P<0.001). Patients with SIBO had significantly lower GFR (P=0.02) and higher liver stiffness (P=0.04) compared to those without SIBO. The presence of SIBO was independently associated with LBP (P=0.007) and PRA (P=0.01). Among patients with SIBO, peak breath hydrogen concentration was significantly correlated with serum LBP (P<0.001), MAP (P<0.001), CO (P=0.008), SVR (P=0.001), PRA (P=0.005), plasma aldosterone (P<0.001), GFR (P<0.001), and liver stiffness (P=0.004). Conclusion: SIBO in patients with cirrhosis and ascites may predispose to greater systemic inflammation, circulatory and renal dysfunction, and more advanced liver fibrosis.

Association of left ventricular diastolic dysfunction with inflammatory activity, renal dysfunction, and liver-related mortality in patients with cirrhosis and ascites.

Left ventricular diastolic dysfunction (LVDD) is the predominant cardiac abnormality in cirrhosis. We investigated the association of LVDD with systemic inflammation and its impact on renal function, occurrence of hepatorenal syndrome (HRS) and survival in patients with cirrhosis and ascites. We prospectively enrolled 215 patients with cirrhosis and ascites. We evaluated the diagnosis and grading of LVDD by Doppler echocardiography, inflammatory markers, systemic hemodynamics, vasoactive factors, radioisotope-assessed renal function and blood flow, HRS development and liver-related mortality. LVDD was diagnosed in 142 (66%) patients [grade 2/3: n  = 61 (43%)]. Serum lipopolysaccharide-binding protein (LBP), plasma renin activity (PRA) and glomerular filtration rate (GFR) were independently associated with the presence of grade 2/3 LVDD and the severity of diastolic dysfunction. Serum tumor necrosis factor-α, cardiac output and plasma noradrenaline were also independently associated with the presence of grade 2/3 LVDD. The diastolic function marker E / e ' was strongly correlated with serum LBP ( r  = 0.731; P  < 0.001), PRA ( r  = 0.714; P  < 0.001) and GFR ( r  = -0.609; P  < 0.001) among patients with LVDD. The 5-year risk of HRS development and death was significantly higher in patients with grade 2/3 LVDD compared to those with grade 1 (35.5 vs. 14.4%; P  = 0.01 and 53.3 vs. 28.2%; P  = 0.03, respectively). The occurrence and severity of LVDD in patients with cirrhosis and ascites is closely related to inflammatory activity. Advanced LVDD is associated with baseline circulatory and renal dysfunction, favoring HRS development, and increased mortality.

Urinary Bladder Carcinoma Demonstrated on Bone Scintigraphy and SPECT/CT Images.

Bone scintigraphy with Tc-99m-diphosphonate analogs are widely used in staging, restaging, and monitoring the therapy effectiveness of various cancer types. Bone-seeking agents are excreted through urination, resulting in the visualization of either anatomical abnormalities or pathological conditions of the kidneys and bladder. We present a case of a 63-year-old man with urinary bladder carcinoma depicted on whole body planar and single-photon emission computed tomography/computed tomography images.

The Role of Myocardial Perfusion Imaging in the Prediction of Major Adverse Cardiovascular Events at 1 Year Follow-Up: A Single Center's Experience.

BACKGROUND: Myocardial perfusion imaging via single-photon emission computed tomography (SPECT MPI) is a well-established method of diagnosing coronary artery disease (CAD). The purpose of this study was to assess the role of SPECT MPI in predicting major cardiovascular events. METHODS: The study population was composed of 614 consecutive patients (mean age: 67 years, 55% male) referred for SPECT MPI due to symptoms of stable CAD. The SPECT MPI was performed using a single-day protocol. We conducted a follow-up on all patients at 12 months via a telephone interview. RESULTS: The majority of our patients (78%) presented findings suggestive of reversible ischemia, fixed defects or both. Extensive perfusion defects were found in 18% of the population, while LV dilation was found in 7%. During the 12-month follow-up, 16 deaths, 8 non-fatal MIs and 20 non-fatal strokes were recorded. There was no significant association of SPECT findings with the combined endpoint of all-cause death, non-fatal MI and non-fatal stroke. The presence of extensive perfusion defects was an independent predictor of mortality at 12 months (HR: 2.90, 95% CI: 1.05, 8.06, p = 0.041). CONCLUSIONS: In a high-risk patient population with suspected stable CAD, only large reversible perfusion defects in SPECT MPI were independently associated with mortality at 1 year. Further trials are needed to validate our findings and refine the role of SPECT MPI findings in the diagnosis and prognosis of cardiovascular patients.

Hamstring Muscle Cramp Visualized on Bone Single-Photon Emission Computed Tomography/Computed Tomography Hybrid Imaging.

ABSTRACT: It is well recognized that bone-seeking radiotracers localize in muscles sustaining an injury from various causes (e.g., strenuous physical activity, trauma, hereditary myopathies, inflammatory myositides, medications, electrical burns, etc.). This report presents the case of an active 50-yr-old man (body mass index = 29) that was recently referred to our nuclear medicine department for bone scintigraphy, for the skeletal staging of a newly diagnosed prostate adenocarcinoma. The scan findings were unremarkable for its oncological indication but revealed extraosseous radiotracer absorption in the medial region of the hamstrings bilaterally. Hybrid scintitomography (single-photon emission computed tomography) with computed tomography indicated that this uptake involved the semitendinosus muscle. On a more meticulous repeat history questioning, he recalled experiencing muscle cramps on both posterior thighs 5 days earlier, during intense work-related physical activity (plumbing) under warm environmental conditions. The combination of strenuous exercise with likely dehydration contributed to bilateral self-limiting heat cramps of the hamstrings, leading to an inconsequential localized minor rhabdomyolysis that was discovered coincidentally a few days later during a bone scan. Although extraskeletal absorption of bone-seeking radiotracers in muscles is widely documented as a result of exertion or injury, this is the first report of radiotracer absorption induced by cramping.

Myocardial perfusion SPECT as a potential mediator on circulating chromogranin A in patients with old myocardial infarction.

OBJECTIVE: Chromogranin A (CgA) is a soluble polypeptide stored within and released from secretory granules of endocrine and other cell types (including cardiomyocytes); CgA appears to be a marker of the overall neuroendocrine activity. Increased levels of serum CgA have been found not only in patients with neuroendocrine neoplasms but also with other malignancies, hypertension, myocardial infarction, heart, or renal failure. SUBJECTS AND METHODS: A population of 307 patients (202 males, 105 females) was enrolled. The study group consisted of 118 individuals (38.4%) with myocardial infarction more than one year old (MI group); the remaining 189 (61.6%) had no known heart disease (control group). All patients underwent myocardial perfusion scintigraphy (MPS) after blood withdrawal for serum CgA measurement. To test whether a possible effect of old infarction on serum CgA is mediated by MPS findings, we employed analysis of covariance for three distinct categories of left ventricular (LV) perfusion deficits as dichotomous predictors: (1) any-type deficits (abnormal MPS); (2) reversible deficits (ischemia); and (3) fixed deficits (scar). RESULTS: In all three MPS conditions, the effect of age, gender, and LV ejection fraction (EFLV) on serum CgA was statistically significant: women exhibited higher CgA levels than men (P=0.008-0.023), whereas increasing age and decreasing EFLV were associated with increasing CgA (all P<0.001). Conversely, no statistically significant differences in mean CgA levels were found between MI patients and normal controls with either abnormal MPS, scar, or ischemia, or their degree and extent. CONCLUSION: Although serum CgA is significantly associated with age, gender, and EFLV in patients with an old MI, no association was found between CgA levels and either old MI history or MPS findings. The verified involvement of circulating CgA in the acute/subacute phase of infarction appears to be blunted in infarctions older than a year.

Assessment of adrenal response in patients with stable cirrhosis and ascites using different short Synacthen tests and definitions.

BACKGROUND AND AIMS: The definition of relative adrenal insufficiency (RAI) in patients with cirrhosis remains controversial. We investigated the serum and salivary cortisol (SalC) response after low-dose and standard-dose Synacthen test in patients with stable cirrhosis and ascites. METHODS: Ninety-five cirrhotic patients with ascites were prospectively evaluated from January 2014 to January 2018. Low-dose [adrenocorticotrophic hormone (ACTH): 1 µg] and standard-dose (ACTH: 250 µg) Synacthen test were successively performed. Paired serum total and saliva cortisol were taken at baseline, 30 min (low-dose test) and 60 min (standard-dose test). Salivary and Δserum total cortisol criteria included post-ACTH SalC < 12.7 ng/ml and/or SalC increase <3 ng/ml and serum total cortisol increase <9 µg/dl, respectively. RESULTS: The prevalence of RAI varied according to the definition used. SalC-defined RAI was significantly more common after low-dose than standard-dose test (54.7% vs. 20%; P < 0.001). Δserum total cortisol-defined RAI was also significantly more frequent after low-dose than standard-dose test (66.3% vs. 24.2%; P < 0.001). Considering low-dose test/SalC criteria as reference diagnostic criteria, standard-dose/salivary and Δserum total cortisol criteria showed low specificity for RAI diagnosis (43.9% and 52.7%, respectively). Survival probability was significantly lower in patients with low-dose test/SalC-defined RAI compared to those without (53.8% vs. 79.1%; P = 0.01). SalC-defined RAI after low-dose test was significantly more common than that defined after standard-dose test (72.7% vs. 30.3%; P < 0.001) among patients who died. CONCLUSION: Low-dose test/SalC definition can identify RAI in about half of patients with stable cirrhosis and ascites and is associated with increased mortality.

Conversion of Propranolol to Carvedilol Improves Renal Perfusion and Outcome in Patients With Cirrhosis and Ascites.

BACKGROUND: In recent years, concerns have been raised on the potential adverse effects of nonselective beta-blockers, and particularly carvedilol, on renal perfusion and survival in decompensated cirrhosis with ascites. We investigated the long-term impact of converting propranolol to carvedilol on systemic hemodynamics and renal function, and on the outcome of patients with stable cirrhosis and grade II/III nonrefractory ascites. PATIENTS AND METHODS: Ninety-six patients treated with propranolol for esophageal varices' bleeding prophylaxis were prospectively evaluated. These patients were randomized in a 2:1 ratio to switch to carvedilol at 12.5 mg/d (CARVE group; n=64) or continue propranolol (PROPRA group; n=32). Systemic vascular resistance, vasoactive factors, glomerular filtration rate, and renal blood flow were evaluated at baseline before switching to carvedilol and after 6 and 12 months. Further decompensation and survival were evaluated at 2 years. RESULTS: During a 12-month follow-up, carvedilol induced an ongoing improvement of systemic vascular resistance (1372±34 vs. 1254±33 dynes/c/cm5; P=0.02) along with significant decreases in plasma renin activity (4.05±0.66 vs. 6.57±0.98 ng/mL/h; P=0.01) and serum noradrenaline (76.7±8.2 vs. 101.9±10.5 pg/mL; P=0.03) and significant improvement of glomerular filtration rate (87.3±2.7 vs. 78.7±2.3 mL/min; P=0.03) and renal blood flow (703±17 vs. 631±12 mL/min; P=0.03); no significant effects were noted in the PROPRA group. The 2-year occurrence of further decompensation was significantly lower in the CARVE group than in the PROPRA group (10.5% vs. 35.9%; P=0.003); survival at 2 years was significantly higher in the CARVE group (86% vs. 64.1%; P=0.01, respectively). CONCLUSION: Carvedilol at the dose of 12.5 mg/d should be the nonselective beta-blocker treatment of choice in patients with cirrhosis and nonrefractory ascites, as it improves renal perfusion and outcome.

False-Positive 18F-PSMA-1007 and True-Negative 18F-Fluorocholine PET/CT Splenic Hemangioma.

A 62-year-old man with prostate cancer underwent both F-PSMA-1007 and F-fluorocholine PET/CT studies for biochemical recurrence. F-PSMA-1007 PET/CT outperformed F-fluorocholine PET/CT in detecting lymph node metastases in the pelvis and retroperitoneum, whereas the former showed a focus of increased uptake in the spleen not seen on F-fluorocholine. The F-PSMA-1007 -avid lesion corresponded to a splenic hemangioma, which was initially detected in an MRI scan 10 years ago, unchanged in size. This case shows different features of F-PSMA-1007 and F-fluorocholine uptake, in an incidentally detected splenic hemangioma, alerting PET/CT reports for possible pitfall.

99mTc-Tetrofosmin Uptake Correlates with the Sensitivity of Glioblastoma Cell Lines to Temozolomide.

99mTc-tetrofosmin (99mTc-TF) is a single-photon emission computed tomography tracer that has been used for brain tumor imaging. The aim of the study was to assess if 99mTc-TF uptake by glioblastoma cells correlates with their response to temozolomide (TMZ). We investigated the correlation of TMZ antitumor effect with the 99mTc-TF uptake in two glioblastoma cell lines. The U251MG cell line is sensitive to TMZ, whereas T98G is resistant. Viability and proliferation of the cells were examined by trypan blue exclusion assay and xCELLigence system. Cell cycle was analyzed with flow cytometry. The radioactivity in the cellular lysate was measured with a gamma scintillation counter. TMZ induced G2/M cell cycle arrest in U251MG cells, whereas there was no effect on cell cycle in T98G cells. Lower 99mTc-TF uptake was observed in U251MG cells that were exposed to TMZ compared to control (P = 0.0159). No significant difference in respect to 99mTc-TF uptake was found in T98G cells when exposed to TMZ compared to control (P = 0.8). With 99mTc-TF, it was possible to distinguish between TMZ-sensitive and resistant glioblastoma cells within 6 h of treatment initiation. Thus, 99mTc-TF uptake may consist a novel approach to assess an early response of glioblastoma to chemotherapy and deserves further investigation.

Comparison of (99m)tc-tetrofosmin and (99m)tc-sestamibi uptake in glioma cell lines: the role of p-glycoprotein expression.

(99m)Tc-Tetrofosmin ((99m)Tc-TF) and (99m)Tc-Sestamibi ((99m)Tc-MIBI) are SPECT tracers that have been used for brain tumor imaging. Tumor's multidrug resistance phenotype, namely, P-glycoprotein (p-gp), and the multidrug resistance related proteins (MRPs) expression have been suggested to influence both tracers' uptake. In the present study we set out to compare (99m)Tc-TF and (99m)Tc-MIBI uptake in high-grade glioma cell lines and to investigate the influence of gliomas p-gp expression on both tracers' uptake. We used four glioma cell lines (U251MG, A172, U87MG, and T98G). The expression of p-gp protein was evaluated by flow cytometry. Twenty µCi (7.4·10(5) Bq) of (99m)Tc-TF and (99m)Tc-MIBI were used. The radioactivity in the cellular lysate was measured with a dose calibrator. P-gp was significantly expressed only in the U251MG cell line (P < 0.001). In all gliomas cell lines (U251MG, U87MG, A172, and T98G) the (99m)Tc-TF uptake was significantly higher than (99m)Tc-sestamibi. The U251MG cell line, in which significant p-gp expression was documented, exhibited the strongest uptake difference. (99m)Tc-TF uptake was higher than (99m)Tc-MIBI in all studied high-grade glioma cell lines. Thus, (99m)Tc-TF may be superior to (99m)Tc-MIBI for glioma imaging in vivo.

A multicenter evaluation of the appropriate use of single-photon emission tomography myocardial perfusion imaging in Greece.

BACKGROUND: This study evaluates the appropriate use of myocardial perfusion imaging (MPI) and determines patterns and variables associated with inappropriate testing. METHODS: Over a 10-month period data were collected prospectively from consecutive patients referred for MPI in four academic departments and an appropriate use grade was assigned (appropriate, uncertain, inappropriate, and unclassifiable scans) according to established criteria. RESULTS: Among 3,032 referrals appropriate MPI had 72.8% of patients and 19.2% of studies were inappropriate, the remaining being uncertain (7.2%) or unclassifiable (0.8%). In multivariate analysis the asymptomatic status (odds ratio 10.7, P < .001), good functional capacity (odds ratio 1.9, P < .001), an interpretable resting electrocardiogram (odds ratio 1.8, P = .004), an age <65 years (odds ratio 1.5, P = .001) and the absence of diabetes (odds ratio 1.7, P < .001) or dyslipidemia (odds ratio 1.3, P = .014) were independent predictors of inappropriate scintigraphy. The most common indication for inappropriate testing was the assessment of asymptomatic patients <2 years after percutaneous coronary intervention (PCI) (38.9%). CONCLUSIONS: The appropriate use of MPI is relatively high, but a considerable proportion of inappropriate scans is noted which is associated with markers of lower risk. The most common source of inappropriate testing is the assessment of asymptomatic patients <2 years after PCI.

Rifaximin improves systemic hemodynamics and renal function in patients with alcohol-related cirrhosis and ascites.

Circulating levels of endotoxin, interleukin (IL)-6, and tumor necrosis factor (TNF)-α increase with intestinal bacterial overgrowth and translocation, and are believed to be involved in the pathogenesis of hyperdynamic circulatory syndrome and functional renal failure in patients with advanced cirrhosis. We investigated the effects of the antibiotic rifaximin on systemic hemodynamics and renal function in patients with alcohol-related cirrhosis and ascites. We measured mean arterial pressure, cardiac output (CO) by Doppler ultrasound, systemic vascular resistance (as the ratio of mean arterial pressure:CO), plasma renin activity, levels of plasma aldosterone, the glomerular filtration rate by plasma clearance of technetium-99m-DTPA, natriuresis, levels of plasma endotoxin, and serum levels of IL-6 and TNF-α in 13 patients at baseline and after 4 weeks of treatment with rifaximin. Rifaximin treatment significantly reduced CO and significantly increased systemic vascular resistance, in association with a significant decrease in plasma rennin activity. The therapy also significantly increased the glomerular filtration rate and natriuresis while reducing levels of endotoxin, IL-6, and TNF-α. Intestinal decontamination with rifaximin improved systemic hemodynamics and renal function in patients with advanced cirrhosis.

Endothelin-B receptors and ventricular arrhythmogenesis in the rat model of acute myocardial infarction.

The arrhythmogenic effects of endothelin-1 (ET-1) are mediated via ETA-receptors, but the role of ETB-receptors is unclear. We examined the pathophysiologic role of ETB-receptors on ventricular tachyarrhythmias (VT/VF) during myocardial infarction (MI). MI was induced by coronary ligation in two animal groups, namely in wild-type (n = 63) and in ETB-receptor-deficient (n = 61) rats. Using a telemetry recorder, VT/VF episodes were evaluated during phase I (the 1st hour) and phase II (2-24 h) post-MI, with and without prior beta-blockade. Action potential duration at 90% repolarization (APD90) was measured from monophasic epicardial recordings and indices of sympathetic activation were assessed using fast-Fourier analysis of heart rate variability. Serum epinephrine and norepinephrine were measured with radioimmunoassay. MI size was similar in the two groups. There was a marked temporal variation in VT/VF duration; during phase I, it was higher (p = 0.0087) in ETB-deficient (1,519 +/- 421 s) than in wild-type (190 +/- 34 s) rats, but tended (p = 0.086) to be lower in ETB-deficient (4.2 +/- 2.0 s) than in wild-type (27.7 +/- 8.0 s) rats during phase II. Overall, the severity of VT/VF was greater in ETB-deficient rats, evidenced by higher (p = 0.0058) mortality (72.0% vs. 32.1%). There was a temporal variation in heart rate and in the ratio of low- to high-frequency spectra, being higher (<0.001) during phase I, but lower (p < 0.05) during phase II in ETB-deficient rats. Likewise, 1 h post-MI, serum epinephrine (p = 0.025) and norepinephrine (p < 0.0001) were higher in ETB-deficient (4.20 +/- 0.54, 14.24 +/- 1.39 ng/ml) than in wild-type (2.30 +/- 0.59, 5.26 +/- 0.67 ng/ml) rats, respectively. After beta-blockade, VT/VF episodes and mortality were similar in the two groups. The ETB-receptor decreases sympathetic activation and arrhythmogenesis during the early phase of MI, but these effects diminish during evolving MI.