Severe Hyponatremia Triggered by Immune Checkpoint Inhibitor Therapy in a Patient With Mulvihill-Smith Syndrome.

Background/Objective: Immune checkpoint inhibitors (ICI), including Programmed Cell Death 1, Programmed Cell Death Ligand 1, and Cytotoxic T-lymphocyte Associated Antigen 4 inhibitors, upregulate T-cell responses against tumor cells and are becoming a cornerstone in the treatment of various advanced solid and hematological cancers. Mulvihill-Smith Syndrome (MSS) is a rare genetic syndrome that has been associated with metabolic abnormalities and early-onset tumors, including malignancies. We report the first known case of ICI-induced hyponatremia attributable to syndrome of inappropriate antidiuretic hormone ADH release (SIADH) in a patient with MSS. Case Report: A 23-year-old female patient with MSS and hepatocellular carcinoma presented with recurrent hyponatremia. Assessment of fluid status and electrolytes revealed a euvolemic, hypotonic process consistent with SIADH shortly after initiating adjuvant therapy with atezolizumab, a Programmed Cell Death Ligand 1 inhibitor. Discussion: Endocrine etiologies for euvolemic hypotonic hyponatremia, including adrenal insufficiency and hypothyroidism, were excluded. The diagnosis of SIADH was confirmed based on electrolyte and osmolality studies. Sodium levels normalized with fluid restriction. Given the onset of hyponatremia 30 days after atezolizumab initiation, we posit that atezolizumab triggered severe hyponatremia due to SIADH. Conclusion: With the expanding utilization of ICIs, including in patients predisposed to malignancies such as MSS, vigilant monitoring for ICI-mediated electrolyte imbalances is crucial. Monitoring for hyponatremia and SIADH in the setting of ICI therapy is recommended.

Intravenous Home Infusion Therapy Instituted From a 24-Hour Clinical Decision Unit For Patients With Cellulitis.

OBJECTIVES: The objective of the study is to evaluate whether patients with cellulitis can be safely discharged from a 24-hour clinical decision unit (CDU) with home infusion of intravenous (IV) antibiotics. METHODS: Clinical decision unit patients receiving IV antibiotics for cellulitis were screened for enrollment in a home infusion therapy (HIT) program. Inclusion criteria were patient ability and willingness to administer IV antibiotics at home and insurers' approval of home infusion services. Patients were discharged home with a peripheral IV and care coordinated with a home infusion provider. RESULTS: Of 213 patients with cellulitis transferred from the emergency department to the CDU over an 8-month study period, a total of 32 (15%) were discharged from the CDU with HIT. The average duration of home IV antibiotic treatment was 3.4 days. There were a total of 9 complications (28%), including IV infiltration (n = 5), allergic reactions (n = 2), nontolerance to the antibiotic (n = 1, this patient developed severe nausea and was switched to oral antibiotics after 2 days of HIT), and 1 patient required readmission for lack of clinical improvement. Among the 181 patients with cellulitis who did not receive HIT, 39 (22%) were hospitalized from the CDU, and 1 additional patient refused admission. CONCLUSIONS: We avoided admission for 31 (97%) of 32 patients who were enrolled in HIT. Home infusion therapy has the potential to prevent hospitalizations, alleviate overcrowding of hospital beds, and decrease health care costs. Further studies are needed to determine the full impact of HIT on CDU patients with acute cellulitis.