Reversible Splenial Lesion Syndrome (RESLES) Following Glufosinate Ammonium Poisoning

Case report: Reversible splenial lesion syndrome caused by diquat poisoning

Diquat (DQ), chemically known as 1,1 '-ethylene-2,2' -bipyridine, is a non-selective herbicide for leaf removal and drying. It has toxic effects on central nervous system cells, and toxic neurological lesions include axonal degeneration and pontine myelolysis. At the same time, DQ can also affect the activity of dopaminergic nerve cells through oxidative stress, causing degeneration and reducing dopamine uptake. With the increasing application of DQ in agricultural production, the clinical reports of neurotoxicity caused by acute DQ poisoning are also increasing. At present, DQ rapid-phase-related toxic encephalopathy mainly involves the pons, midbrain, basal ganglia, thalamus and other brain regions. However, this case is unusual in that the lesion mainly involved the splenium of the corpus callosum. It is also the first time to be reported.

Case report: Autoimmune encephalitis with multiple auto-antibodies with reversible splenial lesion syndrome and bilateral ovarian teratoma

Background

Reversible splenial lesion syndrome (RESLES) is a spectrum of disease radiologically characterized by reversible lesions caused by multiple factors, primarily involving the splenium of the corpus callosum (SCC). The most common causes of RESLES include infection, antiepileptic drug use and withdrawal, and severe metabolic disorders. Nevertheless, cases of autoimmune encephalitis (AE) are uncommon.

Case presentation

A 26-year-old female computer programming engineer with no previous medical or psychiatric history reported to the psychiatric hospital due to a 3-day episode of irritability, babbling, limb stiffness, sleepwalking, hallucinations, and paroxysmal mania. Brain MRI revealed abnormal signals of the SCC. Lumbar puncture was performed and further testing for auto-antibodies was conducted in both the CSF and serum. CSF of the patient was positive for anti-NMDAR (titer of 1:3.2) antibodies, and serum was also positive for anti-NMDAR (titer of 1:32) as well as mGluR5 (titer of 1:10) antibodies. Enhanced CT of the pelvis showed an enlarged pelvic mass; bilateral ovarian teratomas (mature teratoma and immature teratoma) were evaluated, which were pathologically confirmed after transabdominal left adnexal resection, right ovarian biopsy, and ovarian cystectomy. The patient considerably improved after intravenous administration of steroids, immunoglobulin, oral prednisone, surgical treatment, and chemotherapy. A follow-up MRI revealed completely resolved lesions. During a 3-month follow-up, the patient experienced complete resolution of symptoms without any sign of recurrence and tumors. The titer of the anti-NMDAR antibody decreased to 1:10 in serum.

Conclusion

Herein, we report a rare case of AE with overlapping auto-antibodies, along with RESLES and bilateral ovarian teratomas. The current case provides the possibility of the concurrence of mGluR5 antibodies in anti-NMDAR encephalitis. However, the underlying mechanism remains elusive. Furthermore, we provide additional evidence that overlapping antibodies-related pathology may be one of the many causes of RESLES. Nonetheless, caution should be observed in interpreting the observation, considering that this is a single-case study.

Diffusion-Weighted Imaging for Detecting Glufosinate Ammonium Intoxication: A Case Report

Glufosinate ammonium-containing herbicides are non-selective herbicides, used worldwide. With the increasing use of glufosinate ammonium-containing herbicides, cases of acute intoxication in suicide attempts have also increased. Herein, we report a case of a patient presenting cytotoxic edema in the posterior limbs of the bilateral internal capsules, bilateral middle cerebellar peduncles, and splenium of the corpus callosum on the brain diffusion-weighted MRI after glufosinate ammonium intoxication.

Assessment of glufosinate-containing herbicide exposure: A multi-center retrospective study

BACKGROUND

Exposure to glufosinate ammonium, an herbicide used worldwide, can cause CNS and respiratory toxicities. This study aimed to analyze acute human glufosinate ammonium poisoning.

MATERIALS AND METHODS

This multicenter retrospective cohort study involved five medical institutes affiliated with the Chang Gung Memorial Hospital system. Patients with glufosinate ammonium exposure visiting the emergency department (ED) between January 2008 and December 2020 were included.

RESULTS

In total, 95 patients were enrolled. Compared to exposure via the non-oral route, patients exposed orally (n = 61) had lower GCS scores, higher mortality rates, and longer hospital lengths of stay (P-value: <0.001, 0.002, and < 0.001, respectively). In the subgroup analysis among oral exposure patients, the survival group had a lower amount of estimated glufosinate ingestion than the non-survival group (10.5 [3.4-27] vs. 40.5 [27-47.3] g, P-value: 0.022), lower rate of substance co-exposure (9 [19.6%] vs. 10 [66.7%] P-value: 0.001), and lower rate of paraquat co-exposure (0 [0%] vs. 7 [46.7%] P < 0.001) compared with the mortality group. In the orally-exposed and non-paraquat co-exposure patients (n = 54), age > 70 years and GCS score < 9 at triage presented a high sensitivity (100.00%, 95% CI: 63.06-100.00%) and medium specificity (58.70%, 95% CI: 43.23-73.00%) in predicting mortality.

CONCLUSION

Old age, change in consciousness, and paraquat co-exposure were associated with higher mortality in human glufosinate poisoning. Age > 70 years and GCS score < 9 at triage could be predictors of mortality in patients with acute oral glufosinate poisoning.

Prolonged cognitive dysfunction in patient with splenial lesion of the corpus callosum caused by glufosinate ammonium poisoning

Glufosinate ammonium (GLA) is widely used as a commercial herbicide in many countries. Neurotoxicity of GLA has been associated with serious neurological complications such as loss of consciousness, convulsions, and memory impairment. Late-onset memory impairment due to GLA-induced hippocampal lesions is the most distinct clinical feature in GLA poisoning. However, the lesion of the splenium of the corpus callosum (SCC) is a rare condition in GLA poisoning, so the clinical features are not well known. We report the case of a 57-year-old male patient who developed SCC damage after GLA poisoning. The patient had various late-onset neurotoxic symptoms, including prolonged overall cognitive dysfunction and psychosis-like symptoms. Emergency physicians should be aware that GLA-induced SCC lesions may be associated with various late-onset neurotoxic symptoms.

Clinical and imaging features of reversible splenial lesion syndrome with language disorder

Reversible splenial lesion syndrome (RESLES) is a single-stage non-specific syndrome with unclear pathogenesis. There has been no report on answer delay in patients with RESLES. We report a female patient who was admitted to our department for mixed aphasia accompanied by cognitive impairment. During the rapid improvement of aphasia, there was a clear phase of language output response delay accompanied by resolution of imaging lesions. We analyzed the course and the examination results of the patient and speculated the cause and pathogenesis. RESLES-relevant knowledge was systematically reviewed, which will help doctors in the classification of cerebral function and the diagnosis of RESLES. The specific language and cognitive impairment may be associated with the damage of contact fibers in the bilateral primary and secondary sensory and motor cortices.

Reversible Splenial Lesion Syndrome with Some Novel Causes and Clinical Manifestations

Objective Reversible splenial lesion syndrome (RESLES) is a clinical radiological syndrome characterized by a reversible lesion of the splenium of the corpus callosum with a decreased apparent diffusion coefficient (ADC) value. The clinical manifestations of RESLES are diverse. Methods Fifteen cases of adult RESLES patients (10 males and 5 females) were retrospectively selected from the radiology system using the key word "corpus callosum" at a university-affiliated tertiary care hospital between May 1, 2015 and December 31, 2019. The possible precipitating factors, clinicoradiological findings and modified Rankin Scale (mRS) on follow-up were then analyzed. Results The patient ages ranged from 22 to 53 years old. The mean age was 34 years old. The most common neurological symptoms included headache (3/15), dizziness (3/15), first onset of seizure (3/15), paroxysmal blurred vision (2/15), vertigo (2/15), amnesia (2/15), and confused consciousness without seizure (2/15), followed by drowsiness (1/15), paresthesia (1/15), dysmetria (1/15) and dysarthria (1/15). The precipitating factors included infection, seizure, anti-epileptic treatment with levetiracetam, carbamazepine, valproate, hyperglycemia, hypoglycemia, cerebral venous sinus thrombosis, and rabies vaccine injection prior to the onset of RESLES. All cases were carefully followed up and had excellent prognoses. Conclusion RESLES manifests as variety of symptoms with less specificity and precipitating factors. Paroxysmal blurred vision may be a relatively specific symptom of RESLES. Levetiracetam, carbamazepine or valproate could be the cause of RESLES, exposure to the rabies vaccine could be another predisposing factors for RESLES as well. RESLES type 1 was therefore found to be highly "reversible" with an excellent prognosis.

Decreased Glucose Utilization Contributes to Memory Impairment in Patients with Glufosinate Ammonium Intoxication

The symptoms of glufosinate ammonium (GLA) intoxication include gastrointestinal and neurologic symptoms, respiratory failure, and cardiovascular instability. Among these, neurologic symptoms including loss of consciousness, memory impairment, and seizure are characteristic of GLA poisoning. However, the mechanism of brain injury by GLA poisoning is still poorly understood. We investigated nine patients who had performed an F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) scan because of memory impairment caused by GLA ingestion. FDG-PET images of patients with GLA intoxication were compared with 24 age- and sex-matched healthy controls to evaluate whether the patients had abnormal patterns of glucose metabolism in the brain. Decreased glucose metabolism was observed in the inferior frontal and temporal lobes of these patients with GLA intoxication when compared with 24 age- and sex-matched healthy controls. Three patients performed follow-up FDG-PET scans. However, it was shown that the results of the follow-up FDG-PET scans were determined to be inconclusive. Our study showed that memory impairment induced by GLA intoxication was associated with glucose hypometabolism in the inferior frontal and temporal lobes in the brain.

Reversible splenial lesion syndrome associated with dengue fever: a case report

Background

Dengue virus infection in humans can lead to a wide range of clinical manifestations, from mild fever to potentially fatal dengue shock syndrome. The incidence of dengue fever is on the rise in tropical countries. Due to the increasing incidence of dengue fever worldwide, atypical manifestations of the disease are increasingly reported. In this article we report a patient with dengue haemorrhagic fever who presented with reversible splenial lesion syndrome.

Case presentation

A 24-year-old Sri Lankan man who presented with fever and confusion was eventually diagnosed to have reversible splenial lesion syndrome based on brain imaging. Clinical, serological and haematological parameters confirmed a diagnosis of dengue haemorrhagic fever. His presentation, assessment, and management are described in this case report.

Conclusion

Reversible splenial lesion syndrome is a condition which is radiologically characterized by reversible lesion in the splenium of the corpus callosum. It is associated with infectious and non-infectious aetiologies. This case report highlights the occurrence of reversible splenial lesion syndrome as a presenting feature of the expanding list of unusual neurological manifestations of dengue infection.

Reversible splenial lesions presenting in conjunction with febrile illness: a case series and literature review

Transient restricted diffusion and increased T2 signal intensity within the splenium of the corpus callosum is an increasingly recognized albeit uncommon imaging feature in the setting of acute encephalitis and antecedent viral illness. This review will discuss three index cases obtained from an institutional databank. Additionally, the current understanding of the underlying neurophysiologic pathogenesis will be discussed together with differential clinical and imaging diagnostic considerations, treatment options, and outcome metrics.

Reversible splenial lesion syndrome associated with lobar pneumonia: Case report and review of literature

BACKGROUND

Reversible splenial lesion syndrome (RESLES) is a rare clinico-radiological disorder with unclear pathophysiology. Clinically, RESLES is defined as reversible isolated splenial lesions in the corpus callosum, which can be readily identified by magnetic resonance imaging (MRI) and usually resolve completely over a period of time. RESLES could be typically triggered by infection, antiepileptic drugs (AEDs), poisoning, etc. More factors are increasingly recognized.

METHODS AND RESULTS

We reported herein an 18-year-old female patient with lobar pneumonia who developed mental abnormalities during hospitalization. An isolated splenial lesion in the corpus callosum was found by head MRI and the lesion disappeared 15 days later. Based on her clinical manifestations and radiological findings, she was diagnosed with lobar pneumonia associated RESLES. We further summarize the up-to-date knowledge about the etiology, possible pathogenesis, clinical manifestations, radiological features, treatment, and prognosis of RESLES.

CONCLUSION

This report contributes to the clinical understanding of RESLES which may present with mental abnormalities after infection. The characteristic imaging of reversible isolated splenial lesions in the corpus callosum was confirmed in this report. The clinical manifestations and lesions on MRI could disappear naturally after 1 month without special treatment.

Prosopometamorphopsia and alexia following left splenial corpus callosum infarction: Case report and literature review

Background

Lesions to the posterior section of the corpus callosum, called the splenium, and the immediate area have been separately associated with perceived visual distortions of the face (prosopometamorphopsia) or difficulty reading (alexia).

Case report

This case report describes a right-handed patient who complained of prosopometamorphopsia associated with the lower part of the face and alexia following infarction of the left splenium in the corpus callosum.

Conclusions

The splenium and adjacent retrosplenial cortex facilitate the transfer of visual information and memory function between the two hemispheres of the brain and along the Papez circuit, respectively. We believe that damage to this singular area of the brain could bring about several concurrent yet disparate symptoms, such as the reported prosopometamorphopsia and alexia with this patient.