Non-infectious mixed cryoglobulinemia as a new clinical presentation of mutation in the gene encoding coatomer subunit alpha: a case report of two adult sisters

Cryoglobulinemia is a rare disease characterized by the presence of cryoglobulins in the blood serum. It is usually caused by autoimmune, lymphoproliferative, or infectious factors. The pathogenesis of cryoglobulinemia is not well understood, therefore, genetic testing is very important. We present the case of two adult sisters with different clinical phenotypes of non-infectious cryoglobulinemic vasculitis associated with a rare genetic variant [(Hg38) 1:160323529 C>G, NP_004362.2:p.(Gly203Ala)]. One of the sisters suffered from essential mixed cryoglobulinemia, while the other suffered from cryoglobulinemia associated with systemic connective tissue disease. In both cases, genetic tests revealed a variant in the COPA gene, encoding coatomer subunit alpha. Mutations in the COPA gene are associated with COPA syndrome, an autoimmune interstitial lung, joint, and kidney monogenic disease, found mainly in children. Only 15 pathogenic COPA variants have been reported thus far which suggests that the full spectrum of disease manifestations remains unknown. Ours is the first report of the association of the COPA gene with non-infectious cryoglobulinemic vasculitis in adults. This unexpected finding may direct research into the pathogenesis of cryoglobulinemia and new treatment strategies for this rare disease

Factors affecting change in renal function after contrast-enhanced computed tomography in cancer patients

Objectives. Contrast-enhanced computed tomography (CECT) is the most common form of assessing the effectiveness of cancer patient treatment. However, an injection of an iodine-based contrast agent can cause acute kidney damage (AKI). To determine the frequency and factors affecting post-contrast kidney function deterioration during oncological treatment.  Material and methods. Kidney function in cancer patients with solid tumors undergoing a total of 206 CECTs was retrospectively analyzed.  Results. Two hundred and six CECT procedures in 79 patients (age 68.4 ± 10.6 years) were included in the study. The median eGFR before CECT according to the MDRD was 81 mL/min/1.73m2 (IQR 26). The median time between CECT and kidney function examination was 8 (IQR 8) days. In the whole group, the median eGFR change defined as the difference between eGFR after and before CECT was 0.0 (9.0) mL/min/1.73m2 and was not significant. eGFR decreased in 100/206 (48.5%) CECT procedures with the median difference = –5.0 (6.0) mL/min/1.73m2. However, clinically significant deterioration of renal function (an increase in SCr of > 0.3 mg/dL) was found only in two cases (0.9%). The change in eGFR associated with CECT correlated significantly (p < 0.05) with initial creatinine (r = 0.117) and urea (r = 0.158), but not with age and comorbidities. After dividing the analyzed population according to the median GFR, it turned out that in the group of patients with eGFR < 81 mL/min/1.73m2, the median difference in GFR level was 1 (IQR 10), and in the group with a higher eGFR level the median was –1 (IQR 8.5), which was statistically significant (p = 0.03). The multivariate logistic regression analysis in subsequent reduced models confirmed that SCr, uric acid level, and the use of antimetabolites were the factors independently reducing the risk of deterioration of renal function after CECT.  Conclusions. CECT can be responsible for kidney function deterioration; however, it has no impact on oncological treatment

Evaluation of the usefulness of positron emission tomography with [18F]fluorodeoxylglucose performed to detect non-radioiodine avid recurrence and/or metastasis of differentiated thyroid cancer — a preliminary study

Background: About 30% of patients with disseminated differentiated thyroid cancer (DTC) may experience a loss of iodine uptake. It is associated with higher aggressiveness of the tumour and a reduced 10-year survival rate. The diagnosis of non-radioiodine avid DTC metastases remains a diagnostic challenge. A helpful technique for this diagnosis is positron emission tomography with 2-[18F]fluoro-2-deoxy-D-glucose (PET/CT with [18F]FDG). On the other hand, there are still discussions about the clinical value of using exogenous thyroid-stimulating hormone (TSH) stimulation before PET/CT with [18F]FDG. The aim of the study was the assessment of the usefulness of PET/CT with [18F]FDG under TSH suppression and stimulation of TSH performed in the detection of non-radioiodine avid DTC metastases, as well as determination of the thyroglobulin concentration under suppression and stimulation of TSH, which influences the result of PET/CT with [18F]FDG in patients with non-radioiodine avid DTC. Material and methods: Retrospective analysis of 37 PET/CT with [18F]FDG performed in patients with DTC diagnosed and treated at the Department of Endocrinology and Isotope Therapy of the Military Institute of Medicine from January 2018 to July 2020. Of these, PET/CT with [18F]FDG under exogenous rhTSH stimulation was performed in 22 patients and PET/CT with [18F]FDG under TSH suppression in 15 was performed. In all analyzed patients, the result of diagnostic whole-body scintigraphy (WBS) using 80 MBq 131I under rhTSH stimulation was negative, and the concentration of thyroglobulin after stimulation (sTg) was greater than 1.0 ng/mL. Results: In the group of patients examined under TSH suppression, non-radioiodine avid in PET/CT with [18F]FDG were found in 6 out of 15 patients (40%) and in the group of patients examined under rhTSH stimulation in 10 out of 22 patients (45%). The differences between the groups were not statistically significant. The analysis of the receiver operating characteristic (ROC) curves allowed to determine the cut-off point for the positive result of PET/CT performed under TSH suppression with sTg concentration of 11.03 ng/mL. In the group of studies performed under rhTSH stimulation, the cut-off point for sTg was 6.3 ng/mL. There was no statistically significant difference between the baseline thyroglobulin (natTg) and sTg levels and the positive PET/CT result. The administration of rhTSH before the PET/CT examination also had no statistically significant effect on the maximum standard uptake value (SUVmax) of the dominant lesion identified in the PET/CT. Conclusions: 1) PET/CT with [18F]FDG is a useful tool for detection of non-radioiodine avid recurrence and/or metastases of DTC. 2) The concentration of natTg and sTg is highly correlated with a positive result of PET/CT with [18F]FDG. 3) The concentration of natTg is comparable with sTg in predicting a positive result of PET/CT with [18F]FDG. 4) The cut-off point for a positive result of PET/CT for natTg was 1.36 ng/mL and for sTg was 7.05 ng/mL