The co-occurrence of multiple sclerosis and bipolar disorder: A case series on clinical and neuroimaging correlates.

There is a dearth of studies on neuroimaging correlates of Bipolar Disorder (BD) in Multiple Sclerosis (MS). We describe the clinical profile and neuroimaging findings of four cases of MS with BD. Among them, two patients had multiple mood episodes preceding the neurological symptoms, one had concurrent manic and neurological symptoms, and one had multiple depressive episodes and an isolated steroid-induced manic episode. Frontal and temporal lobes, and Periventricular White Matter were involved in all four cases, and hence may be considered biological substrates of BD in MS. Larger studies are needed to validate the utility of these findings.

Adult Onset Episodic Encephalopathy Due to Citrin Deficiency-A Case Report.

Hyperammonemia is a rare cause of adult episodic encephalopathy. Citrin deficiency resulting in citrullinemia type 2 (CTLN2) can lead to recurrent delirium in adults. Here we report a case of adult onset episodic encephalopathy due to citrin deficiency. A 40 years old male presented with one-year history of episodic encephalopathy triggered by high protein and fat diet. He also had chronic pancreatitis and subacute intestinal obstruction which is a novel manifestation of CTLN2. Evaluation showed elevated blood liver enzymes, ammonia, and citrulline. MRI brain showed frontal hyperintensities and bulky basal ganglia which have not been reported. Diagnosis was confirmed by next-generation sequencing which showed a novel variant c. 1591G > A in exon15 of SLC25A13. Hyperammonemic syndromes should be considered in differential diagnosis of episodic encephalopathy in adults. This report shows novel features of subacute intestinal obstruction and MRI findings in CTLN2 expanding spectrum of manifestation.

Case Series of Ethylmalonic Encephalopathy from Southern India.

Ethylmalonic encephalopathy is a rare neurometabolic disorder with central nervous system involvement and vasculopathy. It is presented in infancy with developmental delay, acrocyanosis, petechiae, chronic diarrhea, and early death. This was a retrospective study of confirmed cases of ethylmalonic aciduria from a tertiary care hospital over a period of 5 years from January 2015 to December 2020. Case details including analysis of clinical history, investigations, and outcomes are presented. Of six cases, male-to-female ratio was 4:2. Mean age of presentation was 35.5 months (range: 14-83 months). Consanguinity, global developmental delay, failure to thrive, skin rashes, microcephaly, hypotonia, and exaggerated deep tendon reflexes were observed in all cases. Chronic diarrhea was presented in five cases. The serum levels of C4 carnitine and urinary levels of ethylmalonic acid were increased in all cases. Magnetic resonance imaging (MRI) of the brain showed heterogenous bilateral symmetrical changes in the basal ganglia in five cases, and in one case, MRI could not be done. Genetic testing in two cases showed a homozygous variant in ETHE1 gene. Four children died, while the other two cases showed a decreased in recurrent encephalopathies and diarrhea after starting metronidazole. All children had global developmental delay, failure to thrive, skin rashes, central hypotonia, increased C4 carnitine levels in the serum, and increased ethylmalonic acid in the urine. Chronic diarrhea, acrocyanosis, and basal ganglia change in the MRI of the brain also give important clues for diagnosis. Metronidazole is useful in preventing recurrent episodes of encephalopathy.

Basal Ganglia Autoimmune Encephalitis Following Leptospirosis.

Basal ganglia encephalitis is a part of the spectrum of autoimmune basal ganglia disorders. We are reporting a child who had a fever with focal seizures followed by behavioral problems, rigidity, bradykinesia, and dystonia. His parkinsonism-like features were increasing day by day up to the level that the child was non-ambulatory. His initial Magnetic Resonance Imaging (MRI) of the brain showed asymmetrical T2 hyperintensities involving both the caudate nuclei and putamina. Later, with progressive symptoms, repeat MRI revealed a swelling and symmetrical signal change in both the caudate nuclei and putamina in the form of T2 and Fluid-attenuated inversion recovery (FLAIR) hyperintensities. In addition, there was T2 hyperintensity involving bilateral substantia nigra. Serum basal ganglia antibody, Leptospira Immunoglobulin M (IgM) antibody was positive, and Cerebrospinal Fluid (CSF) oligoclonal band was positive. So, the child was diagnosed with post-leptospirosis autoimmune basal ganglia encephalitis. He was managed with immunomodulatory agents and significant improvement in the symptoms with mild residual extrapyramidal symptoms were noted.

Cribriform Appearance of White Matter in Canavan Disease Associated with Novel Mutations of ASPA Gene.

Cribriform appearance of the brain in Canavan disease is a rare finding. The two presented cases broaden the magnetic resonance imaging (MRI) phenotype wherein numerous oval, cystic structures, a few resembling dilated Virchow-Robin (VR) spaces, were noted in the centrum semiovale, periventricular, and lobar white matter producing a cribriform pattern. Besides, discrete round to oval cysts were present at the gray-white matter junctions in the second case, which were larger and appeared morphologically distinct from the VR spaces. These cysts did not elongate in any plane on imaging and were more representative of giant intramyelinic vacuoles. Genetic analysis revealed novel mutations in the aspartoacylase or ASPA gene that possibly accounts for the severe form of Canavan disease, which probably explains the imaging findings. The multicystic appearance of the white matter in Canavan disease is unusual and possibly represents two different histopathological substrates.

Spectrum of Clinical and Imaging Characteristics of 48 X-Linked Adrenoleukodystrophy Patients: Our Experience from a University Hospital.

Background and Objectives: X-linked adrenoleukodystrophy (X-ALD) occurs due to the mutation in the ABCD1-gene. Our study was to correlate the clinical, radiological, and biochemical features in a cohort of X-ALD patients. Methods: We retrospectively analyzed 48 (M: F: 47:1) biochemically confirmed cases of X-ALD, classified them as cerebral ALD (childhood, adolescent, and adult), adrenomyeloneuropathy, Addisonian only. The Magnetic Resonance Imaging (MRI) of the radiological patterns was classified based on Loes classification. Results: The various clinical phenotypes were childhood cerebral X-ALD (58.3%), adolescent cerebral X-ALD (14.6%), adult-cerebral X-ALD (20.8%), Addisonian variant (4.2%), and adrenomyeloneuropathy (AMN) (2.1%). The imaging features were posterior white matter (Pattern-1) observed in 33 (68.75%) patients, cerebellar white matter (Pattern-4) noted in 5 subjects, anterior white matter (Pattern-2) observed in 3 patients, combined parieto-occipital and frontal white matter (Pattern-5) observed in 3 patients, isolated projection fiber (Pattern-3) observed in 1 patient. Rare features of the involvement of optic tract, anterior and lateral columns of cervicodorsal cord, bilateral central tegmental tracts, basal ganglia, and tigroid appearance were observed. Interpretation: This is a comprehensive clinical, biochemical, and imaging analysis with follow-up information of one of the largest series of X-ALD patients. The knowledge regarding the clinical features, typical and atypical imaging patterns is of vital importance for early diagnosis and treatment.

Rare Treatable Cause of Demyelinating Leukoencephalopathy That One Cannot Afford to Miss.

Biotinidase deficiency is a treatable neurometabolic disorder. It usually presents during the first year of life with seizures, ataxia, hypotonia, vision and hearing disturbance, alopecia, and skin rashes. It can have various neuroimaging findings but demyelinating leukoencephalopathy is an unusual finding in children with biotinidase deficiency that can cause diagnostic challenge as it can radiologically mimic perinatal hypoxic-ischemic encephalopathy or other leukodystrophies. It reverses with early diagnosis and treatment with biotin supplementation and the outcome is rewarding.

Subacute Sclerosing Panencephalitis: Restricted Diffusion and Clinical Evolution.

Background: Subacute sclerosing panencephalitis (SSPE) is a rare entity characterized by a protracted course and progressive neurological deterioration. Objective: We present patterns of diffusion restriction in eight cases of SSPE, a seldom described imaging attribute. Methods: A retrospective analysis was performed on the clinical and neuroimaging data obtained from records of patients with proven SSPE. Patients whose magnetic resonance imaging (MRI) showed evidence of diffusion restriction were included in the analysis. MRI was performed on 3 T and 1.5-T clinical MR systems. Imaging characteristics were reviewed and tabulated by two neuroradiologists. Results: Eight SSPE patients (seven men, one woman; age range: 5-15 years; mean age: 11 years) diagnosed and managed at our institute were included in the analysis. Restricted diffusion was evident in the basal ganglia (n = 3), corpus callosum (n = 2), white matter (n = 2) and in bilateral middle cerebellar peduncles (MCP) (n = 2). One patient had diffusion restriction in the genu of the corpus callosum and bilateral frontal cortical white matter. None of the diffusion-restricted lesions showed contrast enhancement or susceptibility. Six cases fulfilled the diagnostic criteria for fulminant SSPE (fSSPE). The extent of neuroparenchymal involvement was greater in this subset of patients. Conclusions: Restricted diffusion in SSPE, hitherto infrequently described, can indeed occur in both grey and white matter structures and in both supratentorial and infratentorial compartments. Parenchymal diffusion restriction in SSPE possibly reflects an early time point in the clinical evolution. A greater extent of parenchymal diffusion restriction may portend a rapid downhill course, possibly qualifying for fSSPE.

Clinical and Laboratory Profile of Gangliosidosis from Southern Part of India.

Gangliosidoses are progressive neurodegenerative disorders caused by the deficiency of enzymes involved in the breakdown of glycosphingolipids. There are not much data about gangliosidosis in India; hence, this study was planned. The aim is to study the clinical, biochemical, and molecular profile of gangliosidosis. A retrospective chart review, in the pediatric neurology department from January 2015 to March 2020, was performed. Children diagnosed with Gangliosidosis were included. The disorder was confirmed by reduced activity of enzymes and/or pathogenic or likely pathogenic variants in associated genes. We assessed age at presentation, gender, parental consanguinity, clinical manifestations, neuroimaging findings, enzyme level, and pathogenic or likely pathogenic variants. Clinical data for 32 children with gangliosidosis were analyzed, which included 12 (37.5%) with GM1 gangliosidosis, 8 (25%) with Tay-Sachs disease (TSD), 11 (34.37%) with Sandhoff disease (SD), and 1 AB variant of GM2 gangliosidosis that occurs due to GM2 ganglioside activator protein deficiency. Twenty-four (75%) children were the offspring of consanguineous parents. Thirty-one (97%) had developmental delay. The median age at presentation was 15.5 months. Nine (28.12%) had seizures. Five children (41.6%) with GM1 gangliosidosis and two with SD had extensive Mongolian spots. Ten children with GM1 gangliosidosis (83.3%) had coarse facial features. Cherry red spot was found in 24 out of 32 children (75%). All children with GM1 gangliosidosis and none with TSD had hepato-splenomegaly. Two children (2/8; 25%) with TSD and seven (7/11; 63%) with SD had microcephaly. One child with SD had coarse facies and three did not have hepato-splenomegaly. Neuroimaging findings revealed bilateral thalamic involvement in 20 (62.5%) patients and periventricular hypomyelination in all cases. One child had a rare AB variant of GM2 gangliosidosis. GM2 Gangliosidoses are more common compared with GM1 variety. All of them had infantile onset except one child with TSD. Microcephaly can be present while usually megalencephaly is reported in the literature. The absence of hepato-splenomegaly does not rule out SD. Extensive Mongolian spots can be seen in GM2 gangliosidosis. AB variant of GM2 gangliosidosis should be considered when the enzyme is normal in the presence of strong clinical suspicion.

Disorders of Tetrahydrobiopterin Metabolism: Experience from South India.

BACKGROUND: Disorders of tetrahydrobiopterin metabolism represent a rare group of inherited neurotransmitter disorders that manifests mainly in infancy or childhood with developmental delay, neuroregression, epilepsy, movement disorders, and autonomic symptoms. METHODOLOGY: A retrospective review of genetically confirmed cases of disorders of tetrahydrobiopterin metabolism over a period of three years (Jan 2018 to Jan 2021) was performed across two paediatric neurology centres from South India. RESULTS: A total of nine patients(M:F=4:5) fulfilled the eligibility criteria. The genetic variants detected include homozygous mutations in the QDPR(n=6), GCH1(n=2), and PTS(n=1) genes. The median age at onset of symptoms was 6-months(range 3-78 months), while that at diagnosis was 15-months (8-120 months), resulting in a median delay in diagnosis of 9-months. The main clinical manifestations included neuroregression (89%), developmental delay(78%), dystonia(78%) and seizures(55%). Management strategies included a phenylalanine restricted diet, levodopa/carbidopa, 5-Hydroxytryphtophan, and folinic acid. Only, Patient-2 afforded and received BH4 supplementation at a sub-optimal dose later in the disease course. We had a median duration of follow up of 15 months (range 2-48 months). Though the biochemical response has been marked; except for patients with GTPCH deficiency, only mild clinical improvement was noted with regards to developmental milestones, seizures, or dystonia in others. CONCLUSION: Tetrahydrobiopterin deficiencies represent a rare yet potentially treatable cause for non-phenylketonuria hyperphenylalaninemia with better outcomes when treated early in life. Screening for disorders of biopterin metabolism in patients with hyperphenylalaninemia prevents delayed diagnosis. This study expands the genotype-phenotype spectrum of patients with disorders of tetrahydrobiopterin metabolism from South India.

Diffusion and perfusion imaging biomarkers of H3 K27M mutation status in diffuse midline gliomas.

PURPOSE: H3K27M-mutant diffuse midline gliomas (M-DMGs) exhibit a clinically aggressive course. We studied diffusion-weighted imaging (DWI) and perfusion (PWI) MRI features of DMG with the hypothesis that DWI-PWI metrics can serve as biomarkers for the prediction of the H3K27M mutation status in DMGs. METHODS: A retrospective review of the institutional database (imaging and histopathology) of patients with DMG (July 2016 to July 2020) was performed. Tumoral apparent diffusion coefficient (ADC) and peritumoral ADC (PT ADC) values and their normalized values (nADC and nPT ADC) were computed. Perfusion data were analyzed with manual arterial input function (AIF) and leakage correction (LC) Boxerman-Weiskoff models. Normalized maximum relative CBV (rCBV) was evaluated. Intergroup analysis of the imaging variables was done between M-DMGs and wild-type (WT-DMGs) groups. RESULTS: Ninety-four cases (M-DMGs-n = 48 (51%) and WT-DMGs-n = 46(49%)) were included. Significantly lower PT ADC (mutant-1.1 ± 0.33, WT-1.23 ± 0.34; P = 0.033) and nPT ADC (mutant-1.64 ± 0.48, WT-1.83 ± 0.54; P = 0.040) were noted in the M-DMGs. The rCBV (mutant-25.17 ± 27.76, WT-13.73 ± 14.83; P = 0.018) and nrCBV (mutant-3.44 ± 2.16, WT-2.39 ± 1.25; P = 0.049) were significantly higher in the M-DMGs group. Among thalamic DMGs, the min ADC, PT ADC, and nADC and nPT ADC were lower in M-DMGs while nrCBV (corrected and uncorrected) was significantly higher. Receiver operator characteristic curve analysis demonstrated that PT ADC (cut-off-1.245), nPT ADC (cut-off-1.853), and nrCBV (cut-off-1.83) were significant independent predictors of H3K27M mutational status in DMGs. CONCLUSION: DWI and PWI features hold value in preoperative prediction of H3K27M-mutation status in DMGs.

FDG-PET in Autoimmune Encephalitis: Utility, Pattern of Abnormalities, and Correlation with Autoantibodies.

Background: Fluorodeoxyglucose-positron emission tomography (FDG-PET) in autoimmune encephalitis (AE) as an adjunctive investigation helps in characterizing the type of AE based on characteristic metabolic patterns. Objectives: We aimed to study the following: (i) the sensitivity of FDG-PET in the diagnosis of AE, (ii) describe abnormal patterns of metabolism of various subtypes of AE, and (iii) correlate serum serology with FDG-PET abnormalities. Materials and Methods: This study was conducted at a tertiary university hospital in South India. The demographic profile, clinical features, and investigations (FDG-PET, magnetic resonance imaging (MRI) brain, electroencephalography (EEG), cerebrospinal fluid (CSF)) were reviewed. The nuclear medicine physician performed blinded qualitative visual and semi-quantitative analysis of the 18-FDG-PET (fluorine 18-FDG-PET) findings of these patients. Results: Twenty-nine (M:F: 11:18) patients were recruited; among them, 22 (75.8%) patients had autoimmune antibodies; the rest seven (24.1%) patients were seronegative. Among the 22 seropositive patients, 9 (31%) patients were positive for anti-N-methyl-D-aspartate receptor (NMDAR), 8 (28%) for anti-leucine-rich glioma inactivated 1 (LGI-1), 4 (14%) for anti-contactin-associated protein 2 (CASPR2), 1 (3%) for anti-glutamic acid decarboxylase (GAD)-65, and rest 7 (24%) patients were seronegative. The patterns most commonly observed were isolated hypermetabolism (41%), isolated hypometabolism (41%), and combined hypermetabolism with hypometabolism (18%). The fraction of abnormalities was lower for MRI (17/22; 73.9%) than for FDG-PET (27/29; 93.1%). FDG-PET correlated with serology in 10 (34%) cases [NMDAR: 6 (60%) and LGI-1: 4 (40%)]. The sensitivity of FDG-PET was 94.1% when compared with MRI. Discussion and Conclusion: FDG-PET correlated with serology in only one-third of patients. The most consistent pattern in both seropositive and seronegative AE is characterized by parieto-occipital hypometabolism and fronto-temporal with basal ganglia hypermetabolism.