We compared functional imaging modalities including PET with 6-¹⁸F-fluorodopamine (¹⁸F-DA) with ¹²³I-metaiodobenzylguanidine (¹²³I-MIBG) and somatostatin receptor scintigraphy (SRS) with ¹¹¹In-pentetreotide in nonmetastatic and metastatic pheochromocytoma (PHEO). Methods: We studied 25 men and 28 women (mean age ± SD, 44.2 ± 14.2 y) with biochemically proven nonmetastatic (n = 17) or metastatic (n = 36) PHEO. Evaluation included anatomic imaging with CT or MRI and functional imaging that included at least 2 nuclear medicine modalities: ¹⁸F-DA PET, ¹²³I-MIBG scintigraphy, or SRS. Sensitivity of functional imaging versus anatomic imaging was assessed on a per-patient and a per-region basis. Results: For this available cohort, on a per-patient basis overall sensitivity (combined for nonmetastatic and metastatic PHEO) was 90.2% for ¹⁸F-DA PET, 76.0% for ¹²³I-MIBG scintigraphy, and 22.0% for SRS. On a per-region basis, overall sensitivity was 75.4% for ¹⁸F-DA PET, 63.4% for ¹²³I-MIBG scintigraphy, and 64.0% for SRS. Conclusion: If available, ¹⁸F-DA PET should be used in the evaluation of PHEO, because it is more sensitive than ¹²³I-MIBG scintigraphy or SRS. If ¹⁸F-DA PET is not available, ¹²³I-MIBG scintigraphy (for nonmetastatic or adrenal PHEO) and SRS (for metastatic PHEO) should be the first alternative imaging methods to be used.

[¹³¹I]meta-iodobenzylguanidine ([¹³¹I]MIBG) is the most commonly used treatment for metastatic pheochromocytoma and paraganglioma. It enters the chromaffin cells via the membrane norepinephrine transporter; however, its success has been modest. We studied the ability of histone deacetylase (HDAC) inhibitors to enhance [¹²³I]MIBG uptake by tumors in a mouse metastatic pheochromocytoma model. HDAC inhibitors are known to arrest growth, induce differentiation and apoptosis in various cancer cells, and further inhibit tumor growth. We report the in vitro and in vivo effects of two HDAC inhibitors, romidepsin and trichostatin A, on the uptake of [³H]norepinephrine, [¹²³I]MIBG, and [¹⁸F]fluorodopamine in a mouse model of metastatic pheochromocytoma. The effects of both inhibitors on norepinephrine transporter activity were assessed in mouse pheochromocytoma (MPC) cells by using the transporter-blocking agent desipramine and the vesicular-blocking agent reserpine. HDAC inhibitors increased [³H]norepinephrine, [¹²³I]MIBG, and [¹⁸F]fluorodopamine uptake through the norepinephrine transporter in MPC cells. In vivo, inhibitor treatment resulted in significantly increased uptake of [¹⁸F]fluorodopamine positron emission tomography (PET) in pheochromocytoma liver metastases (19.1±3.2% injected dose per gram of tumor (%ID/g) compared to liver metastases in pretreatment scans 5.9±0.6%; P<0.001). Biodistribution analysis after inhibitors treatment confirmed the PET results. The uptake of [¹²³I]MIBG was significantly increased in liver metastases 9.5±1.1% compared to 3.19±0.4% in untreated control liver metastases (P<0.05). We found that HDAC inhibitors caused an increase in the amount of norepinephrine transporter expressed in tumors. HDAC inhibitors may enhance the therapeutic efficacy of [¹³¹I]MIBG treatment in patients with advanced malignant pheochromocytoma and paraganglioma.

Micronutrient supplementation is recommended in Ebola virus disease (EVD); however, there are limited data on therapeutic impacts of specific micronutrients. To evaluate the association between vitamin A supplementation and mortality in EVD. This retrospective cohort included patients with EVD admitted to 5 International Medical Corps Ebola Treatment Units (ETUs) in 2 countries during 2014–2015. Protocolized treatments with micronutrients were used at all ETUs: however, because of resource constraints, only a subset of patients received vitamin A. Standardized data on demographics, clinical characteristics, malaria status, and Ebola viral loads (cycle threshold values) were collected. The outcome of interest was mortality between cases treated with 200,000 IU of vitamin A on care days 1 and/or 2, and those not. Propensity scores based on the first 48 h of care were derived using covariates of age, ETU duration, malaria status, cycle threshold values, and clinical symptoms. Patients were matched 1:1 using nearest neighbors with replacement. Mortality between cases treated and not treated with vitamin A was compared using generalized estimating equations to calculate RR with associated 95% CI. There were 424 cases analyzed, of which 330 (77.8%) were treated with vitamin A. The mean age was 30.5 y and 40.3% were men. The most common symptoms were diarrhea (85.6%), anorexia (80.7%), and abdominal pain (76.9%). Mortality proportions among cases treated and not treated with vitamin A were 55.0% and 71.9%, respectively. In the propensity-matched analysis, mortality was significantly lower among cases receiving vitamin A (RR = 0.77, 95% CI: 0.59, 0.99; P = 0.041). In a subgroup analysis of patients treated with multivitamins already containing vitamin A, additional vitamin A supplementation did not impact mortality. Early vitamin A supplementation was associated with reduced mortality in patients with EVD, and should be further studied and considered for use in future epidemics.

Vaccine hesitancy among displaced populations is associated with inequitable access to services and mistrust of authorities, among other factors. This study evaluated variations in attitudes toward COVID-19 vaccines and factors associated with vaccine acceptance among refugees and Lebanese nationals accessing 60 International Medical Corps-supported health facilities through two cross-sectional surveys pre- (n = 3927; Survey 1) and post- (n = 4174; Survey 2) vaccine rollout. Logistic regression was used to assess predictors of vaccine acceptance using the health beliefs model. Refugees comprised 52.9% (Survey 1) and 54.2% (Survey 2) of respondents. Vaccine acceptance was low among both groups in Survey 1 (25.9% refugees vs. 23.1% Lebanese nationals), but higher in Survey 2 in Lebanese (57.6%) versus refugees (32.9%). Participants reported greater perceived benefits of vaccination, higher perceived COVID-19 susceptibility, and lower perceived vaccination barriers in Survey 2 versus Survey 1. Post-vaccine rollout, refugees had lower odds of vaccine acceptance compared to Lebanese (OR 0.50, 95%CI 0.41–0.60), while older age (OR 1.37, 95%CI 1.06–1.78, ≥51 years vs. 18–30 years) was associated with greater vaccine acceptance. Health beliefs model variables were associated with vaccine acceptance in both surveys. Tailored strategies to respond dynamically to changes in vaccine attitudes among vulnerable groups in Lebanon are essential for equitable vaccine uptake.