Laboratory reference intervals influence referral patterns for hemoglobin abnormalities in the Ontario virtual care system.

This retrospective cross-sectional study investigates the impact of laboratory-specific hemoglobin reference intervals on electronic consultation (eConsult) referral patterns for suspected anemia and elevated hemoglobin at a tertiary care center in London, Ontario that serves Southwestern Ontario. The study analyzed referrals through the Ontario Telemedicine Network's eConsult platform for hemoglobin abnormalities, excluding patients under 18 years old, between July 1, 2019, and June 30, 2023.The main outcome measures were influence of hemoglobin reference intervals on the referral patterns for suspected anemia and elevated hemoglobin, as well as the extent of pre-referral laboratory testing. Of the 619 eConsults reviewed, 251 referrals for suspected anemia and 93 for elevated hemoglobin were analyzed. Referral patterns showed significant variance in hemoglobin levels based on different laboratory thresholds. Referrals for suspected anemia in females from laboratories whose lower limit was 120 g/L or greater had a hemoglobin concentration 7.5 g/L greater than referrals that used laboratories with a threshold lower than 120 g/L. The study also identified potential areas for improvement in pre-referral investigations; 44% of eConsults did not provide a ferritin level, 53% were missing a B12 level, and 81% were missing a reticulocyte count. In conclusion, laboratory reference intervals for hemoglobin significantly influence referral patterns for suspected hemoglobin abnormalities in Ontario's eConsult system. There is a need for standardized reference intervals and comprehensive pre-referral testing to avoid unnecessary medicalization and referrals. We propose an anemia management algorithm to guide primary care providers in the pre-referral investigation process.

Carotid intima-medial thickness in patients with severe hypertriglyceridemia.

Background and aims: Severe hypertriglyceridemia (HTG), defined as plasma triglyceride (TG) concentration > 10 mmol/L, is relatively uncommon, and its implications for atherosclerotic cardiovascular disease (ASCVD) risk remain somewhat unclear. We evaluated the association between severe HTG and carotid intima-media thickness (IMT), a marker for ASCVD. Methods: We studied three clinical cohorts: 88 patients with severe HTG (mean TG level 20.6 mmol/L), 271 patients with familial hypercholesterolemia (FH) as a contrast group, and 70 normolipidemic controls. Carotid IMT was measured using standardized ultrasound imaging. Statistical analysis was conducted using one-way analysis of variance (ANOVA) to compare mean IMT values, analysis of covariance (ANCOVA) to adjust for confounding variables, specifically age and sex, as well as Spearman pairwise correlation analysis between variables. Results: Unadjusted mean carotid IMT was greater in severe HTG and FH groups compared to controls, however, this was no longer significant for severe HTG after adjustment for age and sex. In contrast, adjusted carotid IMT remained significantly different between the FH and control groups. Conclusions: Our findings suggest that extreme TG elevations in severe HTG patients are not significantly associated with carotid IMT, in contrast to the increased IMT seen in FH patients. These findings add perspective to the complex relationship between severe HTG and ASCVD risk.

Pericardial Extramedullary Hematopoiesis Associated with Metastatic Adenocarcinoma of Gastrointestinal or Pancreaticobiliary Origin: A Case Report.

Extramedullary hematopoiesis (EMH) is a rare complication of solid tumor malignancies. We describe the first case of a patient who developed EMH in the pericardium secondary to metastatic gastrointestinal or pancreaticobiliary cancer. A 58-year-old man presented with recurrent episodes of fatigue and shortness of breath and was treated with thoracocentesis and pericardiocentesis for pleural and pericardial effusions, respectively. Owing to a markedly elevated alkaline phosphatase, a bone scan was performed and demonstrated diffuse sclerotic lesions. Evaluation of pleural effusion diagnosed metastatic adenocarcinoma, and cytospin morphology of the pericardial fluid demonstrated EMH. While EMH secondary to solid tumors is commonly suggested to be due to cytokine signaling, we propose the mechanism of EMH in this patient was due to extensive disruption of bone marrow hematopoiesis, similar to what is seen in myeloproliferative neoplasms.