Clinical Impact of Antipolyethylene Glycol (PEG) Antibody in Hematological Patients Administered PEGylated-Granulocyte Colony-Stimulating Factor.

Polyethylene glycol (PEG) is a polymer covalently attached to proteins to improve their half-life and efficacy. We previously reported that the PEGylated granulocyte colony-stimulating factor (PEG-G-CSF) is immunogenic, which could adversely impact drug efficacy and safety in animal models. Here, we analyzed the relationship between anti-PEG antibody titers and the clinical impact of PEG-G-CSF in 19 hematological patients. A gradual decrease of anti-PEG antibody titers from baseline was observed after PEG-G-CSF administration. Of the 19 participants, 10 were assessed for noninfectious fever after the first administration of PEG-G-CSF and three experienced this reaction. The receiver operating characteristic curve revealed that the cut-off values of pretreated anti-PEG IgM and IgG titers for noninfectious fever were set at 5.0 and 96.6 U/mL, respectively. All patients who experienced noninfectious fever had anti-PEG antibody titers above this cut-off value (P = .033). An enzyme-linked immunosorbent assay revealed that some anti-PEG antibodies in patients with anti-PEG antibody titers above the cut-off value reacted with the PEGylated liposome. These results indicate the reactivity of the anti-PEG antibodies to PEGylated therapeutics observed in hematologic patients and the possibility of the relationship between high titers of anti-PEG antibodies and the development of adverse events after PEG-G-CSF administration.

A Case of Superior Mesenteric Vein Thrombosis That Was Difficult to Diagnose and Caused Acute Deterioration / 日本農村医学会雑誌

A 68-year-old man presented with abdominal pain, vomiting, and diarrhea. He was admitted with a provisional diagnosis of acute gastroenteritis based on physical examination, blood tests, ultrasonography, and plain computed tomography. Despite treatment with fasting and fluid replacement, cardiopulmonary arrest occurred the following morning. All attempts at resuscitation failed and the patient died. Pathological autopsy revealed the presence of clots within the superior mesenteric vein, which was diagnosed as superior mesenteric vein thrombosis. This rare disease often manifests with only nonspecific symptoms and is typically difficult to diagnose. Because delayed diagnosis may lead to unfavorable outcomes, it is important to include this disease in the differential diagnosis of abdominal pain.