Adult Mesenteric Lymphangioma Resulting in Small Bowel Obstruction.

A mesenteric cystic lymphangioma (MCL) is a rare condition that primarily manifests in children. This case report illustrates an unusual presentation of an MCL causing a small bowel obstruction with volvulus in an adult. We present a 31-year-old male who presented to our hospital with a small bowel obstruction. He underwent laparotomy, and a lymphatic mass acting as a lead point and causing small bowel volvulus was discovered intra-operatively. The patient underwent a small bowel with associated mass resection and primary anastomosis; he recovered well. The final pathology demonstrated an MCL. Despite the MCL being a rare entity in adults, it must be considered as the differential for various abdominal pathologies. Although the majority of these masses lack malignant potential, they should be resected, as they pose a risk of mechanical obstruction, torsion, and perforation. Prior descriptions include individual case reports of symptomatic lesions, proposed non-operative management, and follow-up imaging.

Factors associated with delays in medical and surgical open facial fracture management.

Objectives: Open fractures are at risk of infection because of exposure of bone and tissue to the environment. Facial fractures are often accompanied by other severe injuries, and therefore fracture management may be delayed until after stabilization. Previous studies in this area have examined timing of multiple facets of care but have tended to report on each in isolation (eg, antibiotic initiation). Methods: This was a retrospective study of adult patients admitted to five trauma centers from January 1, 2017 to March 31, 2021 with open facial fractures. Variables collected included demographics, injury mechanism, details on facial and non-facial injuries, facial fracture management (irrigation and debridement (I&D), irrigation without debridement, open reduction internal fixation (ORIF), antibiotics), and other hospital events. The study hypothesized that the presence of serious non-facial injuries would be associated with delays in facial fracture management. The primary aims were to describe open facial fracture management practices and examine factors associated with early versus delayed fracture management. A secondary aim was to describe infection rates. Early treatment was defined as within 24 hours of arrival for I&D, irrigation without debridement, and ORIF and within 1 hour for antibiotics. Results: A total of 256 patients were included. Twenty-seven percent had major trauma (Injury Severity Score ≥16). The presence of serious head injury/traumatic brain injury was associated with delayed I&D (ORearly=0.04, p<0.01), irrigation without debridement (ORearly=0.09, p<0.01), and ORIF (ORearly=0.10, p<0.01). Going to the OR within 24 hours was associated with early I&D (ORearly=377.26, p<0.01), irrigation without debridement (ORearly=13.54, p<0.01), and ORIF (ORearly=154.92, p<0.01). The infection rate was 4%. Conclusions: In this examination of multiple aspects of open facial fracture management, serious injuries to non-facial regions led to delays in surgical fracture management, consistent with the study hypothesis. Level of evidence: Level III, prognostic/epidemiological.

Role of bicarbonate supplementation on urine uric acid crystals and diabetic tubulopathy in adults with type 1 diabetes.

Uricosuria and crystallization are increasingly recognized risk factors for diabetic tubulopathy. This pilot clinical trial aimed to determine the acute effect of urinary alkalinization using oral sodium bicarbonate (NaHCO3 ) on UA crystals in adults with type 1 diabetes (T1D). Adults with T1D, ages 18 to 65 years (n = 45, 60% female, HbA1c, 7.5 ± 1.2%, 20.2 ± 9.3 years duration) without chronic kidney disease (eGFR ≥60 mL/min/1.73 m2 and albumin-to-creatinine ratio < 30 mg/g) received 2 doses of 1950 mg oral NaHCO3 over 24 hours. Fasting urine and serum were collected pre- and post-intervention. UA crystals were identified under polarized microscopy. Urine measurements included: osmolality, pH, UA, creatinine and kidney injury molecule-1 (KIM-1). NaHCO3 therapy increased mean ± SD urine pH from 6.1 ± 0.7 to 6.5 ± 0.7 (P < .0001). Prior to therapy, 31.0% of participants had UA crystals vs 6.7% post therapy (P = .005). Change in urine pH inversely correlated with change in urine KIM-1 (r:-0.51, P = .0003). In addition, change in urine UA over 24 hours correlated with change in urine KIM-1 (r:0.37, P = .01). In conclusion, oral NaHCO3 normalized urine pH and decreased UA crystals, and may hold promise as an inexpensive and safe tubulo-protective intervention in individuals with T1D.

Phosphorylation of thymidine and AZT in heart mitochondria: elucidation of a novel mechanism of AZT cardiotoxicity.

Antiretroviral nucleoside analogs used in highly active antiretroviral therapy (HAART) are associated with cardiovascular and other tissue toxicity associated with mitochondrial DNA depletion, suggesting a block in mitochondrial (mt)-DNA replication. Because the triphosphate forms of these analogs variably inhibit mt-DNA polymerase, this enzyme has been promoted as the major target of toxicity associated with HAART. We have used isolated mitochondria from rat heart to study the mitochondrial transport and phosphorylation of thymidine and AZT (azidothymidine, or zidovudine), a component used in HAART. We demonstrate that isolated mitochondria readily transport thymidine and phosphorylate it to thymidine 5'-triphosphate (TTP) within the matrix. Under identical conditions, AZT is phosphorylated only to AZT-5'-monophosphate (AZT-MP). The kinetics of thymidine and AZT suggest negative cooperativity of substrate interaction with the enzyme, consistent with work by others on mitochondrial thymidine kinase 2. Results show that TMP and AZT-MP are not transported across the inner membrane, suggesting that AZT-MP may accumulate with time in the matrix. Given the lack of AZT-5'-triphosphate (AZT-TP), it seems unlikely that the toxicity of AZT in the heart is mediated by AZT-TP inhibition of DNA polymerase gamma. Rather, our work shows that AZT is a potent inhibitor of thymidine phosphorylation in heart mitochondria, having an inhibitory concentration (IC)(50) of 7.0 +/- 0.9 microM. Thus, the toxicity of AZT in some tissues may be mediated by disrupting the substrate supply of TTP for mt-DNA replication.