Q fever is a zoonotic bacterial infection caused by Coxiella burnetii. Chronic Q fever comprises less than five percent of all Q fever cases and, of those, endocarditis is the most common presentation (up to 78% of cases), followed by vascular involvement. Risk factors for chronic Q fever with vascular involvement include previous vascular surgery, preexisting valvular defects, aneurysms, and vascular prostheses. The most common symptoms of chronic Q fever with vascular involvement are nonspecific, including weight loss, fatigue, and abdominal pain. Criteria for diagnosis of chronic Q fever include clinical evidence of infection and laboratory criteria (antibody detection, detection of Coxiella burnetii DNA, or growth in culture). Treatment of chronic Q fever with vascular involvement includes a prolonged course of doxycycline and hydroxychloroquine (≥18 months) as well as early surgical intervention, which has been shown to improve survival. Mortality is high in untreated chronic Q fever. We report a case of chronic Q fever with vascular involvement in a 77-year-old man with prior infrarenal aortic aneurysm repair, who lived near a livestock farm in the southeastern United States.

Purpose: To Evaluate the correlation between tumor dosimetric parameters with objective tumor response (OR) and overall survival (OS) in patients with surgically unresectable colorectal liver metastasis (CRLM) undergoing resin-based Ytrrium-90 selective internal radiation therapy (Y90 SIRT). Materials and Methods: 45 consecutive patients with CRLM underwent resin-based Y90 SIRT in one or both hepatic lobes (66 treated lobes total). Dose volume histograms were created with MIM Sureplan® v.6.9 using post-treatment SPECT/CT. Dosimetry analyses were based on the cumulative volume of the five largest tumors in each treatment session and non-tumoral liver (NTL) dose. Receiver operating characteristic (ROC) curve was used to evaluate tumor dosimetric factors in predicting OR by Response Evaluation Criteria for Solid Tumors at 3 months post-Y90. Additionally, ROC curve was used to evaluate non-tumoral liver dose as a predictor of grade ≥3 liver toxicity and radioembolization induced liver disease (REILD) 3 months post Y90. To minimize for potential confounding demographic and clinical factors, univariate and multivariate analysis of survival with mean tumor dose as one of the factors were also performed. Kaplan-Meier estimation was used for OS analysis from initial Y90 SIRT. Results: 26 out of 45 patients had OR with a median OS of 17.2 months versus 6.8 months for patients without OR (p < 0.001). Mean tumor dose (TD) of the five largest tumors was the strongest predictor of OR with an area under the curve of 0.73 (p < 0.001). Minimum TD, and TD to 30%, 50%, and 70% of tumor volume also predicted OR (p’s < 0.05). Mean TD ≥ 100 Gy predicted a significantly prolonged median OS of 19 vs. 11 months for those receiving.

Qualitative assessment of PET/CT results in post therapy is very important to provide a reproducible and systemic reporting. A recently introduced response criteria, known as the Hopkins criteria showed promising results. Our aim is to externally validate the Hopkins interpretation system to assess therapy response in head and neck squamous cell cancer (HNSCC). The study included 69 biopsy proven HNSCC patients who underwent post therapy PET/CT between 5-24 weeks after completion of therapy. PET/CT images were interpreted by one nuclear medicine physician and one nuclear radiologist, independently. The studies were scored according to the Hopkins criteria for right neck, left neck, primary tumor site, and overall assessment. Scores 1, 2, 3 were considered as negative and scores 4 and 5 were considered as positive for tumors. Inter-reader variability was assessed using percent agreement and Kappa statistics. Progression-free survival (PFS) was estimated using the Kaplan-Meier method and analyzed using Cox proportional hazards regression. Of the 69 patients, 59 (85.5%) were males, with a mean age of 62.8 years. The percent agreement between readers for overall, right neck, left neck, and primary tumor site were 91.3%, 97.6%, 97.6%, 91.3% respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of the overall therapy assessment were 66.7%, 87.3%, 33%, 96.5% respectively. Cox univariate regression analysis showed positive primary tumor site scores and overall scores were associated with a higher risk of progression (p<0.05). External validation of Hopkins criteria showed excellent inter-reader agreement and prediction of PFS in HNSCC patients.