[A case of bromadiolone poisoning leading to digestive tract, abdominal hemorrhage and secondary paralytic ileus].

Bromadiolone, commonly known as super warfarin, is a long-acting coumarin dicoumarin rodenticide. The mechanism of bromadiolone is mainly to inhibit vitamin K1 epoxide reductase and affect the synthesis of coagulation factors Ⅱ, Ⅶ, Ⅸ and Ⅹ, which causes blood coagulation dysfunction and systemic multiple organ hemorrhage. Here, we report of a case of bromadiolone poisoning patient who had digestive tract, abdominal hemorrhage, as well as secondary paralytic ileus. After blood product transfusion and vitamin K1 supplementation, the patient was discharged after the physical condition was improved. It's suggestied that clinicians should pay attention to rare complications to prevent missed diagnosis when treating other bromadiolone poisoning.

Enteric plexus neuropathy associated with PD-L1 blockade in a patient with small-cell lung cancer.

Immune checkpoint inhibitors have revolutionized the management of patients with cancer. The increasing use of these agents has brought up a new set of adverse events which are widely heterogenous and potentially life-threatening. Rare immune-related adverse events associated with nervous system have not been described thoroughly, but their early recognition and management may be crucial. Immune-related autonomic neuropathy may be presented with a constellation of symptoms ranging from gastrointestinal and urinary complaints, to sweating and hypotension. Intestinal pseudo-obstruction as consequence of immune-related myenteric autonomic neuropathy is an under-recognized, not-well described and potentially fatal adverse event. We herein, present a unique case of enteric plexus neuropathy induced by PD-L1 blockade in a patient with small-cell lung cancer.

Lay abstract Immunotherapy with immune checkpoint inhibitors has improved the life expectancy in many cancer patients. However, the stimulation of immune system to fight cancer may also affect healthy tissues, bringing about the risk of adverse events. These adverse events may affect almost every organ system of the body and may vary from mild to life-threatening. Immunotherapy-related damage to nervous plexuses, which supply the guts with nerves, has been reported only in a small number of cases. The symptoms usually mimic those of gut inflammation, including diarrhea, constipation, abdominal distension, and vomiting. Upon these symptoms, enteric nervous system toxicity should be considered. Early recognition and management are crucial to stop further neurological damage. We present a rare case of enteric nerve damage in a patient with small-cell lung cancer treated with immunotherapy.

Chronic intestinal pseudo-obstruction in a patient with metastatic gastro-oesophageal junction cancer receiving treatment with pembrolizumab.

Acute gastrointestinal (GI) immune-related adverse events (irAE) are commonly reported by patients with cancer undergoing treatment with immune checkpoint inhibitors (CPI); however chronic irAEs are rare. We present a case of a 71-year-old woman with metastatic gastro-oesophageal junction (GOJ) adenocarcinoma who developed delayed-onset chronic intestinal pseudo-obstruction (CIPO) while receiving second-line pembrolizumab. Repeated CT scans of the abdomen/pelvis found no small bowel obstruction, and evaluations for bowel inflammation, infection and paraneoplastic syndrome were negative. Bowel rest and glucocorticoids were associated with transient symptom resolution; however, symptoms recurred within 1 month. The patient was ultimately supported with total parenteral nutrition and intestinal motility agents. After 4 months, the GOJ cancer remained stable with no signs of progression. As CPI use expands, the incidence of rare irAEs, such as CIPO, may increase.

Fatal enteric plexus neuropathy after one dose of ipilimumab plus nivolumab: a case report.

BACKGROUND: Immune checkpoint inhibitors (ICIs) are the treatment of choice for several cancers and can be associated with remarkable clinical benefit, but can also cause serious immune-related adverse events (irAEs). Management of rare and severe irAEs is challenged by an incomplete knowledge of their natural history and pathogenetic mechanisms. We report a case of fatal acute-onset gastro-intestinal (GI) hypomotility from myenteric plexus neuropathy following a single dose of ipilimumab plus nivolumab given for treatment of Merkel cell carcinoma (MCC). CASE PRESENTATION: A 66-year-old man with recurrent metastatic MCC involving several organs (liver, bones and disseminated retroperitoneal lymphadenopathy) developed profound pharyngeal dysphagia and ileus that started 7 days after receiving a single administration of combination immune checkpoint blockade consisting of nivolumab (3 mg/kg) and low-dose ipilimumab (1 mg/kg). A swallowing study showed oropharyngeal dysfunction and aspiration. Imaging studies were consistent with diffuse intestinal paresis. An extensive work-up did not reveal obvious causes of these symptoms, and enteric plexopathy was suspected. Empiric immune suppressive therapy was initiated urgently. Despite an escalating immunosuppressive regimen that included high dose steroids, tacrolimus and therapeutic plasma exchange, no improvement in GI motility was seen and the patient suffered repeated episodes of aspiration. Seven weeks after the onset of GI hypomotility, the patient succumbed to sepsis from intestinal perforations. At autopsy, histologic specimens obtained from the entire GI tract (pharynx to rectum) showed near complete loss of ganglion cells within the myenteric and submucosal plexuses. An associated inflammatory infiltrate was not seen, suggesting a 'burned out' phase of illness. C4d complement deposition was found at the ganglionic sites, suggesting antibody-mediated pathogenesis. Remarkably, at sites of previously suspected Merkel cell metastases, no residual viable Merkel cell carcinoma was identified. CONCLUSIONS: GI-tract paresis due to myenteric neuritis is a rarely reported toxicity of ICIs. Because the window of reversibility is likely to be very brief, quick and decisive interventions are warranted. Subtle functional and anatomic perturbations of the myenteric nervous system from the use of ICIs may be more prevalent than realized and should be suspected and addressed in both clinical and investigational settings.

Risk of Opioid-Related Adverse Events After Primary and Revision Total Knee Arthroplasty.

Postoperative analgesia after primary total knee arthroplasty (TKA) and revision knee arthroplasty (RKA) can be reliant on the use of opioids and may lead to opioid-related adverse events (ORAEs). This study evaluated the risk of ORAEs following TKA and RKA using the 5% Medicare claims (2010-2013) database. There were 41,702 TKA and 3817 RKA patients who met the inclusion criteria. At 90 days, respiratory complications were the most common complication (TKA: 6.12%; RKA: 8.01%), followed by postoperative nausea and vomiting (TKA: 2.86%; RKA: 3.95%), and urinary retention complications (TKA: 2.79%; RKA: 3.20%). For TKA, risk factors for respiratory complications included older age, lower socioeconomic status, more comorbidities, obesity, chronic obstructive pulmonary disease, white race, and patients in the Midwest and West (vs. South) (p 002). The average Medicare payment for treating complications within 90 days of a TKA was $6206 and $6222 following RKA. Awareness risks for ORAEs in select patients can assist in developing a multimodal postoperative pain control and patient education protocols. (Journal of Surgical Orthopaedic Advances 27(2):148-154, 2018).

Oxaliplatin-induced enteric neuronal loss and intestinal dysfunction is prevented by co-treatment with BGP-15.

BACKGROUND AND PURPOSE: Gastrointestinal side effects of chemotherapy are an under-recognized clinical problem, leading to dose reduction, delays and cessation of treatment, presenting a constant challenge for efficient and tolerated anti-cancer treatment. We have found that oxaliplatin treatment results in intestinal dysfunction, oxidative stress and loss of enteric neurons. BGP-15 is a novel cytoprotective compound with potential HSP72 co-inducing and PARP inhibiting properties. In this study, we investigated the potential of BGP-15 to alleviate oxaliplatin-induced enteric neuropathy and intestinal dysfunction. EXPERIMENTAL APPROACH: Balb/c mice received oxaliplatin (3 mg·kg-1 ·day-1 ) with and without BGP-15 (15 mg·kg-1 ·day-1 : i.p.) tri-weekly for 14 days. Gastrointestinal transit was analysed via in vivo X-ray imaging, before and after treatment. Colons were collected to assess ex vivo motility, neuronal mitochondrial superoxide and cytochrome c levels and for immunohistochemical analysis of myenteric neurons. KEY RESULTS: Oxaliplatin-induced neuronal loss increased the proportion of neuronal NO synthase-immunoreactive neurons and increased levels of mitochondrial superoxide and cytochrome c in the myenteric plexus. These changes were correlated with an increase in PARP-2 immunoreactivity in the colonic mucosa and were attenuated by BGP-15 co-treatment. Significant delays in gastrointestinal transit, intestinal emptying and pellet formation, impaired colonic motor activity, reduced faecal water content and lack of weight gain associated with oxaliplatin treatment were restored to sham levels in mice co-treated with BGP-15. CONCLUSION AND IMPLICATIONS: Our results showed that BGP-15 ameliorated oxidative stress, increased enteric neuronal survival and alleviated oxaliplatin-induced intestinal dysfunction, suggesting that BGP-15 may relieve the gastrointestinal side effects of chemotherapy.

[Paralytic ileus with fatal consequence under psychotropic medication]. / Paralytischer Ileus mit Todesfolge unter Psychopharmakotherapie.

In the area of Bielefeld there occurred a striking accumulation of four cases of death as a consequence of a paralytic ileus within a period of two years. All four patients suffered from a psychotic disorder and had taken psychotropic medication for many years. After exclusion of other causes, the anticholinergic effect of the psychotropic medication must be taken as the cause of death. A review of literature and pharmacological receptor profiles are presented. Therapeutic consequences are described in order to prevent more cases of death.

Strategy to reduce bortezomib-induced paralytic ileus in patients with myeloma and impaired renal function.

While bortezomib is known to cause adverse effects involving the autonomic nervous system, gastrointestinal side effects are typically mild. We describe herein a series of patients with myeloma and impaired renal function who developed severe paralytic ileus secondary to bortezomib use. Our patients had other risk factors for paralytic ileus including electrolyte abnormalities and opiate use. The striking commonality in our patients is the development of paralytic ileus with intravenous bortezomib in the setting of reduced renal function, followed by ileus resolution with bortezomib dose reduction. We discuss the existing literature on this subject and propose a strategy in order to reduce the risk of paralytic ileus in these patients. Upfront bortezomib dose reduction to 1 mg/m2 intravenously in patients with myeloma with a glomerular filtration rate (GFR) of <30 mL/min may prevent paralytic ileus, while not compromising the clinical outcomes. Our conclusions will have to be validated in larger studies.

Role of oxidative stress in oxaliplatin-induced enteric neuropathy and colonic dysmotility in mice.

BACKGROUND AND PURPOSE: Oxaliplatin is a platinum-based chemotherapeutic drug used as a first-line therapy for colorectal cancer. However, its use is associated with severe gastrointestinal side-effects resulting in dose limitations and/or cessation of treatment. In this study, we tested whether oxidative stress, caused by chronic oxaliplatin treatment, induces enteric neuronal damage and colonic dysmotility. EXPERIMENTAL APPROACH: Oxaliplatin (3 mg·kg-1 per day) was administered in vivo to Balb/c mice intraperitoneally three times a week. The distal colon was collected at day 14 of treatment. Immunohistochemistry was performed in wholemount preparations of submucosal and myenteric ganglia. Neuromuscular transmission was studied by intracellular electrophysiology. Circular muscle tone was studied by force transducers. Colon propulsive activity studied in organ bath experiments and faeces were collected to measure water content. KEY RESULTS: Chronic in vivo oxaliplatin treatment resulted in increased formation of reactive oxygen species (O2 -), nitration of proteins, mitochondrial membrane depolarisation resulting in the release of cytochrome c, loss of neurons, increased inducible NOS expression and apoptosis in both the submucosal and myenteric plexuses of the colon. Oxaliplatin treatment enhanced NO-mediated inhibitory junction potentials and altered the response of circular muscles to the NO donor, sodium nitroprusside. It also reduced the frequency of colonic migrating motor complexes and decreased circular muscle tone, effects reversed by the NO synthase inhibitor, Nω-Nitro-L-arginine. CONCLUSION AND IMPLICATIONS: Our study is the first to provide evidence that oxidative stress is a key player in enteric neuropathy and colonic dysmotility leading to symptoms of chronic constipation observed in oxaliplatin-treated mice.

Vincristine-induced paralytic ileus during induction therapy of treatment protocols for acute lymphoblastic leukemia in adult patients.

Vincristine (VCR) is an important drug used in the treatment of acute lymphoblastic leukemia (ALL). VCR-induced neurotoxicity can manifest as peripheral neuropathy, constipation, or paralytic ileus. While there are some case reports describing VCR-induced paralytic ileus (VIPI) in pediatric ALL, there are fewer publication on adult ALL patients. Therefore, we retrospectively investigated VIPI during induction therapy of treatment protocols for ALL in 19 adult patients. The incidence of VIPI was 32%. VIPI was significantly increased in patients receiving concomitant itraconazole (ITCZ) (p = 0.04). We recommend avoidance of the combination of VCR and ITCZ.

Glucagon-like peptide 2 counteracts the mucosal damage and the neuropathy induced by chronic treatment with cisplatin in the mouse gastric fundus.

BACKGROUND: Glucagon-like peptide-2 (GLP-2) is a pleiotropic hormone synthesized and secreted by the enteroendocrine 'L' cells able to exert intestine-trophic and anti-inflammatory effects. The antineoplastic drug cisplatin causes gastrointestinal alterations with clinical symptoms (nausea and vomiting) that greatly affect the therapy compliance. Experimentally, it has been reported that chronic cisplatin treatment caused mucosal damage and enteric neuropathy in the rat colon. METHODS: We investigated, through a combined immunohistochemical and functional approach, whether [Gly(2) ]GLP-2, a GLP-2 analog, was able to counteract the detrimental effects of long-term cisplatin administration in the mucosa and myenteric neurons of mouse gastric fundus. KEY RESULTS: Morphological experiments showed a reduction in the epithelium thickness in cisplatin-treated mice, which was prevented by [Gly(2) ]GLP-2 co-treatment. Immunohistochemistry demonstrated that cisplatin caused a significant decrease in myenteric neurons, mainly those expressing neuronal nitric oxide synthase (nNOS), that was prevented by [Gly(2) ]GLP-2 co-treatment. In the functional experiments, [Gly(2) ]GLP-2 co-treatment counteracted the increase in amplitude of the neurally induced contractions observed in strips from cisplatin-treated animals. The NO synthesis inhibitor L-N(G) -nitro arginine caused an increase in amplitude of the contractile responses that was greater in preparations from cisplatin+[Gly(2) ]GLP-2 treated mice compared to the cisplatin-treated ones. CONCLUSIONS & INFERENCES: The results demonstrate that in cisplatin long-term treated mice [Gly(2) ]GLP-2 is able to counteract both the mucosal gastric fundus damage, by preventing the epithelium thickness decrease, and the neuropathy, by protecting the nNOS neurons. Taken together, the present data suggest that [Gly(2) ]GLP-2 could represent an effective strategy to overcome the distressing gastrointestinal symptoms present during the anti-neoplastic therapy.

Paralytic ileus following "subcutaneous bortezomib" therapy: focus on the clinical emergency-report of two cases.

We retrospectively analyzed the medical history of 19 elderly myeloma patients treated with the "novel subcutaneous formulation of bortezomib." In our experience, two patients (10 %) discontinued treatment for paralytic ileus. The exact pathogenetic mechanisms of toxic megacolon and paralytic ileus due to "novel subcutaneous formulation of bortezomib" are unclear. Probably, it may be related to possible damage of the autonomic nerve fibers that control organ functions. Adequate prevention and management of the gastrointestinal (GI) toxicities with the use of fluid intake and prokinetic and laxative drugs (at least two types of agents in a suboptimal dose) especially in patients with risk factors for GI side effects (anti-myeloma novel agents, opioids or antiemetics, iron supplements, spinal and cord compression, immobility, history of constipation) can decrease the possibility of interruption of administration of drug and increase adherence to treatment. Clearly this complication must be borne in mind whenever a patient develops acute abdominal pain and distension.

Structural and functional consequences of buserelin-induced enteric neuropathy in rat.

BACKGROUND: Women treated with gonadotropin-releasing hormone (GnRH) analogs may develop enteric neuropathy and dysmotility. Administration of a GnRH analog to rats leads to similar degenerative neuropathy and ganglioneuritis. The aim of this study on rat was to evaluate the early GnRH-induced enteric neuropathy in terms of distribution of neuronal subpopulations and gastrointestinal (GI) function. METHODS: Forty rats were given the GnRH analog buserelin (20 µg, 1 mg/ml) or saline subcutaneously, once daily for 5 days, followed by 3 weeks of recovery, representing one treatment session. Two weeks after the fourth treatment session, the animals were tested for GI transit time and galactose absorption, and fecal weight and fat content was analyzed. After sacrifice, enteric neuronal subpopulations were analyzed. Blood samples were analyzed for zonulin and antibodies against GnRH and luteinizing hormone, and their receptors. RESULTS: Buserelin treatment transiently increased the body weight after 5 and 9 weeks (p < 0.001). Increased estradiol in plasma and thickened uterine muscle layers indicate high estrogen activity. The numbers of both submucous and myenteric neurons were reduced by 27%-61% in ileum and colon. The relative numbers of neurons containing calcitonin gene-related peptide (CGRP), cocaine- and amphetamine-related transcript (CART), galanin, gastrin-releasing peptide (GRP), neuropeptide Y (NPY), nitric oxide synthase (NOS), serotonin, substance P (SP), vasoactive intestinal peptide (VIP) or vesicular acetylcholine transporter (VAchT), and their nerve fiber density, were unchanged after buserelin treatment, but the relative number of submucous neurons containing somatostatin tended to be increased (p = 0.062). The feces weight decreased in buserelin-treated rats (p < 0.01), whereas feces fat content increased (p < 0.05), compared to control rats. Total GI transit time, galactose absorption, zonulin levels in plasma, and antibody titers in serum were unaffected by buserelin treatment. CONCLUSIONS: A marked enteric neuronal loss with modest effects on GI function is found after buserelin treatment. Increased feces fat content is suggested an early sign of dysfunction.