"Burnt-out" progressive multifocal leukoencephalopathy in idiopathic CD4+ lymphocytopenia.

Progressive multifocal leukoencephalopathy (PML) is a fatal disease caused by John Cunningham virus (JCV) infection; however, a growing number of PML patients now survive longer and achieve remission, largely due to the advent of combination antiretroviral therapy. Several reports have suggested that the pathology in such patients presents only chronic demyelination without characteristic cellular changes, being referred to as "burnt-out" PML. On the other hand, our knowledge of "burnt-out" PML is still substantially limited, especially in patients with non-human immunodeficiency virus infection. Here, we report a case of PML associated with idiopathic CD4+ lymphocytopenia (ICL) who presented with spontaneous remission and survived for 11 years after onset. Notably, postmortem examination revealed surprisingly broad "burnt-out" lesions lacking the classic histopathological findings. However, pathogenic JCV-specific DNA sequences was still present in the autopsied brain tissue. This case suggests that complete remission can be achieved with a persistent presence of JCV-specific pathogenic sequences, even after a catastrophic infection. Considering that there have been a few reported cases of PML with ICL with long survival, the long-term survival of our case may share a favorable immunological response that is unique to a subgroup of ICL.

[A case of transient global amnesia associated with painless myocardial infarction].

A 66-year-old woman with a history of hypertension complained about sudden short-term memory loss. On arrival to our outpatient clinic, she was alert and oriented and did not have chest pain or shortness of breath. Neurological and neuropsychological examinations were within normal limits. In light of a transient anterograde amnestic attack and no neurological focal deficit, we clinically diagnosed transient global amnesia (TGA). To confirm whether there was an intracranial lesion or not, diffusion-weighted MRI of the brain was performed, and revealed hyper-intense lesions in the left hippocampus and right corpus callosum. Consequently, the patient was admitted to our hospital on follow-up for suspected cerebral infarction. On day 1, laboratory tests indicated an elevated troponin I level, and electrocardiogram revealed an inverted T wave in the inferior leads. Coronary angiography on day 9 of admission demonstrated severe stenosis of the right coronary artery, leading to a diagnosis of non-ST elevation myocardial infarction. Although TGA itself typically has a favorable prognosis, clinicians should consider potential concurrent painless myocardial infarction in patients with TGA.

Rotatory Vertigo Caused by a Small Hemorrhage in the Superior Temporal Gyrus.

Rotatory vertigo is known to have not only peripheral causes, e.g., Meniere's disease, vestibular neuritis, and benign paroxysmal positional vertigo, but also central causes, e.g., stroke, hemorrhage, and tumor. In most cases, central rotatory vertigo is caused by a lesion in the brainstem or cerebellum, but rare cases with a cerebral lesion have also been reported. We herin describe a unique case with acute rotatory vertigo following a small hemorrhage in the left superior temporal gyrus, which probably led to a dysfunction of the visual-vestibular system.

Characterization of Sporadic Creutzfeldt-Jakob Disease and History of Neurosurgery to Identify Potential Iatrogenic Cases.

We previously reported a phenotype of Creutzfeldt-Jakob disease (CJD), CJD-MMiK, that could help identify iatrogenic CJD. To find cases mimicking CJD-MMiK, we investigated clinical features and pathology of 1,155 patients with diagnosed sporadic CJD or unclassified CJD with and without history of neurosurgery. Patients with history of neurosurgery more frequently had an absence of periodic sharp-wave complexes on electroencephalogram than patients without a history of neurosurgery. Among 27 patients with history of neurosurgery, 5 had no periodic sharp-wave complexes on electroencephalogram. We confirmed 1 case of CJD-MMiK and suspected another. Both had methionine homozygosity at codon 129 of the prion protein gene and hyperintensity lesions in the thalamus on magnetic resonance images of the brain, which might be a clinical marker of CJD-MMiK. A subgroup with a history of neurosurgery and clinical features mimicking dura mater graft-associated CJD might have been infected during neurosurgery and had symptoms develop after many years.

[A case of acute leukoencephalopathy induced by a combination of 5-fluorouracil and metronidazole].

We describe a 66-year-old woman who received folinic acid, leucovorin, fluorouracil and oxaliplatin for advanced rectal carcinoma. These drugs were initiated on day 1, and a pelvic abscess was identified on day 7. Piperacillin-tazobactam was initially administered, but was changed to ceftriaxone and metronidazole on day 14 on the basis of antimicrobial susceptibility testing. On the following day, the patient reported blindness, and MRI of the brain showed signal abnormalities in the splenium of the corpus callosum on DWI, suggestive of metronidazole encephalopathy. Although the total body exposure was 2 g, metronidazole was discontinued. The patient developed coma a few days later, and MRI of the brain on day 26 showed high signal intensity extensively involving the white matter in the cerebrum as well as the brainstem and cerebellum. She died 37 days after the initial administration of the chemotherapy. Pathological studies demonstrated decreased staining intensity in the myelin sheath and multiple vacuolar alterations, consistent with toxicity induced by metronidazole and fluorouracil. Care should be taken when administering a combination of these drugs, even if the total body exposure to each drug is limited.

[A case of primary central nervous system anaplastic lymphoma kinase positive anaplastic large cell lymphoma manifested as a unilateral pachymeningits].

There have been 23 reports of primary central nervous system anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma in the literature. Here we report the 24th case of a 40-year-old man who presented with occipital headache for one month. His contrast-enhanced brain MRI showed enhancement around the right temporal lobe, which suggested a diagnosis of hypertrophic pachymeningitis. He improved with steroid therapy. After discharge, however, he was readmitted with generalized convulsive seizures. Finally, he was diagnosed as primary central nervous system ALK-positive anaplastic large cell lymphoma by brain biopsy. Primary central nervous system lymphoma invading dura matter can rarely manifests as a unilateral pachymeningitis. Therefore, in case of pachymeningitis, we should pay attention to the possibility of infiltration of lymophoma with meticulous clinical follow-up.

[Mononeuritis multiplex due to thrombotic ischemia of primary antiphospholipid antibody syndrome without vasculitis: an autopsy case report].

The patient was a 78-year-old man. Three years before admission, he developed transient peripheral neuropathy and purpura, and at admission, he presented with livedo reticularis of both his lower extremities and with mononeuritis multiplex. Vasculitis was not observed, and antiphospholipid antibodies were detected. The nerve and skin biopsies revealed no inflammation; axonal degeneration accompanied by thrombi was found in his arterioles and venules. Based on these findings, he was diagnosed with ischemic peripheral neuropathy due to primary antiphospholipid syndrome. Administration of anticoagulant therapy resulted in an improvement in symptoms; however, two months later, a relapse occurred, and the patient contracted an infection while undergoing immunosuppressive therapy. The infection became fulminant, and the patient succumbed to multiple organ failure. The autopsy revealed a systemic arterial and venous embolism; however, no vasculitis was observed. Antiphospholipid syndrome, which is responsive to antithrombotic treatment, should be considered as a differential diagnosis of mononeuritis multiplex.

[Small cerebellar vascular lesion can produce isolated conjugate deviation of the eyes].

The cerebellum has almost never been considered responsible for conjugate deviation of the eyes (CDE). A few cases of CDE caused by cerebellar lesions without the involvement of the brainstem have been reported, but the lesions were too large to evaluate their localization in the cerebellum. In this report, we describe 2 cases of isolated CDE caused by small cerebellar vascular lesions and a case of CDE and staggering gait that occurred following cerebellar infarction. We further describe cases of head rotation without CDE and those of vertigo without CDE or head rotation due to a similar small lesion. Case 1: A 73-year-old woman with rheumatism was brought to our department because of sudden-onset of difficulty in looking to the right. She was admitted 3 hours after onset; at admission she was alert and well-oriented and denied both vertigo and nausea. Neurologic examination revealed CDE to the left; however, no limb ataxia was detected. Diffusion-weighted MRI showed a small infarction in the white matter of the right PICA area near the vermis. Her CDE disappeared spontaneously within 2 days. Case 2: A 79-year-old man with hypertension exhibited CDE to the right without vertigo or ataxia following a small hemorrhage in the cerebellan area mentioned in Case 1. Case 3: A 65-year-old man with hypertension presented with CDE to the right and staggering gait after a small infarction in an area lateral to that mentioned above. The first 2 cases suggest that a small cerebellar vascular lesion can produce isolated CDE to the side contralateral to the lesion. The region responsible for CDE in these cases was located in the white matter of the PICA area near the vermis, although similar lesions in Cases 4 and 5 produced no CDE.