Leukoencephalopathy, cerebral calcifications, and cysts: A clinical case involving a long-term follow-up and literature review

Leukoencephalopathy with Cerebral Calcifications and Cysts: The Neurosurgical Perspective. Literature Review

BACKGROUNDS

Labrune syndrome is a rare white matter disease characterized by angiomatous leukoencephalopathy, diffuse intracranial calcifications and supratentorial and infratentorial parenchymal cysts. The clinical worsening is often related to cyst expansion, and surgery may be advocated for symptomatic management in about one third of cases. However, no consensus exists on the surgical timing, the most effective procedure, and the long-term results.

METHODS

Electronic databases PubMed/MEDLINE and Google Scholar were searched for studies published up to April 2022 using the search string (Labrune syndrome OR leukoencephalopathy with calcifications and cysts OR brain calcifications OR brain cysts) AND (therapy OR surgery).

RESULTS

We found 28 studies in the literature, and we added a new case from our institution, comprising 37 patients. All the patients in this series underwent surgical intervention. We reviewed all the pertinent literature to discuss clinical-radiological features and etiopathogenesis, specifically addressing the surgical options, clinical results, and prognosis.

CONCLUSIONS

Leukoencephalopathy with cerebral calcifications and cysts is a rare neurodegenerative disorder for which effective medical treatment is lacking. Surgery remains the only therapeutic option to control the disease to reduce the mass effect of growing cystic lesions. Almost half of the patients who underwent surgery required further approaches, with great concern for the associated disabilities. Several procedures have been described, with no evidence regarding which procedure is the most effective. Individual-based surgical planning must be advocated, tailoring the approach to limit side effects. Mini-invasive neuroendoscopic approaches may be considered to achieve satisfactory results.

Leukoencephalopathy with calcifications and cysts: A case report with literature review

Leukoencephalopathy with calcifications and cysts (LCC; OMIM #614561) is a rare disease and at present there are less than 100 cases reported worldwide. Mutations in the SNORD118 gene is now known to be the cause of LCC. We present a case who was heterozygous for the n.70G>A and n.6C>T sequence variants of the SNORD118 gene, variants which to date have not been described. Compared with the cases that we reviewed, our patient had the second longest time to diagnosis (age 56) from onset of symptoms 40 years prior. Moreover, his cousin's family has a high prevalence of epilepsy. This paper reviewed all published reports to date that had descriptive cases involving LCC as well as testing for the SNORD118 gene. Since 1996 only 85 patients have been described in 59 case reports. In this review, we summarize their clinical features, especially central nervous system symptoms, treatment, pathology, and gene testing results.

Leukoencephalopathy with brain calcifications and cysts (Labrune syndrome) case report: diagnosis and management of a rare neurological disease

Background

Leukoencephalopathy with brain calcifications and cysts (LCC; also known as Labrune syndrome) is a rare genetic microangiopathy caused by biallelic mutations in SNORD118. The mechanisms by which loss-of-function mutations in SNORD118 lead to the phenotype of leukoencephalopathy, calcifications and intracranial cysts is unknown.

Case presentation

We present the histopathology of a 36-year-old woman with ataxia and neuroimaging findings of diffuse white matter abnormalities, cerebral calcifications, and parenchymal cysts, in whom the diagnosis of LCC was confirmed with genetic testing. Biopsy of frontal white matter revealed microangiopathy with small vessel occlusion and sclerosis associated with axonal loss within the white matter.

Conclusions

These findings support that the white matter changes seen in LCC arise as a consequence of ischemia rather than demyelination.

Paediatric neurosurgical implications of a ribosomopathy: illustrative case and literature review

Ribosomopathies are rare, recently defined entities. One of these, Labrune syndrome, is recognisable radiologically by its distinctive triad of leukoencephalopathy, intracranial calcifications and cysts (LCC). These cysts may have neurosurgical implications at different ages because of their progressive expansion and local mass effect. The aetiology of LCC is related to a widespread cerebral microangiopathy and is due to a genetic mutation in SNORD118, responsible for stabilisation of the large ribosomal subunit during assembly.

Neuroimaging findings in leukoencephalopathy with calcifications and cysts: case report and review of the literature

Leukoencephalopathy with cerebral calcifications and cysts (LCC) is a neurological disorder characterized by the radiological triad of white matter abnormalities, intracranial calcifications and cystic lesions variable in size resulting from a diffuse cerebral microangiopathy. Typically, progressive focal neurological deficits and seizures are the first clinical manifestation, but the severity of symptoms can vary according to the size and location of the cystic lesions holding compressive effects on the surrounding brain tissue. The most common histopathological finding is diffuse microangiopathy, which might be associated to pathogenic mutations in SNORD118 gene causing Labrune syndrome. Similar neuroradiological appearances have been found in the Coats plus syndrome, a systemic disorder caused by a genetic diffuse microangiopathy that affects not only the brain but also the retina and multiple organs, with a more complex clinical picture that address the diagnosis; biallelic mutations in CTC1 gene, encoding the conserved telomere maintenance component 1 (CTC1), are responsible of this systemic disorder. The aim of this contribution is to review the existing literature focusing on the neuroimaging characteristics by reporting cases in which radiological findings were highly suggestive for LCC.

Case Report: Clinical Features of Childhood Leukoencephalopathy With Cerebral Calcifications and Cysts Due to SNORD118 Variants

Background: Leukoencephalopathy with cerebral calcifications and cysts (LCC) is a rare autosomal recessive cerebral microangiopathy. Recently, biallelic variants in a non-protein-coding gene SNORD118 have been discovered to cause LCC.

Case Presentation: We here report a genetically confirmed childhood case of LCC. The patient was a 4-year-and-1-month-old boy with focal seizures. The age at onset of his seizure was 10 days after birth. The seizures were well-controlled by antiepileptic treatment but reoccurred twice due to a head impact accident and a fever, respectively. He suffered from a self-limited esotropia and unsteady running gait during the seizure onset. He had the typical neuroimaging triad of multifocal intracranial calcifications, cysts, and leukoencephalopathy. Genetic analysis indicated that he carried compound heterozygous variants of n.^*9C>T and n.3C>T in SNORD118, which were inherited from his parents.

Conclusion: We report a childhood LCC case with compound heterozygous variants in SNORD118. To the best of our knowledge, the patient reported in our case had the youngest onset age of LCC with a determined genotype. The triad cerebral-imaging findings of calcifications, cysts, and leukoencephalopathy provide a crucial diagnostic basis. Moreover, the gene assessment, together with the clinical investigations, should be considered for the diagnosis of LCC.

Surgical considerations in Labrune syndrome

PURPOSE

Labrune syndrome (LS) is a rare white matter disease characterized by leukoencephalopathy with intracranial calcification and cysts (LCC). While the intracranial cyst characteristics of LS are for the most part stable, some may require surgical intervention when they develop associated hemorrhage and/or mass effect. To date, no review of the surgical outcomes of cyst decompression in LS has been performed.

CASE PRESENTATION

We report the case of a 16-year-old girl with LS who presented with progressive right hemiparesis from an enlarging hemorrhagic left thalamic cyst. The patient underwent frameless stereotactic cyst aspiration and Ommaya reservoir placement and her hemiparesis subsequently improved. Serial monitoring demonstrated stable decompression of the cyst.

CONCLUSIONS

The pathophysiology of LS is thought to be diffuse cerebral microangiopathy and it is thought that these microhemorrhages contribute to the formation of intracranial cysts as well as diffuse calcifications. Indications for surgical intervention in LS are not well established and the heterogeneity of lesions compels them to be managed on a case-by-case basis. Based on our literature review, surgery is the standard treatment of choice for patients with progressive symptoms and growing lesions on imaging studies, with outcomes favoring less-invasive stereotactic approaches with contingencies of reservoir placement when cysts recur.

18F-FDG PET/CT in Labrune Syndrome

A 69-year-old woman presented with cognitive impairment related to attentive, executive, and mnemonic functions; progressive worsening of walking, speaking, writing, and reading ability; and double sphincter incontinence. Leukoencephalopathy, cystic lesions, and calcifications, suspected for Labrune syndrome, were observed at MRI and CT brain images. Generalized wave abnormalities were also visible at electroencephalogram. Functional brain imaging performed with F-FDG PET/CT demonstrated a decreased glucose metabolism in impaired brain regions, in accordance with MRI findings. Genetic testing confirmed a mutation of SNORD118.

Adult-onset leukoencephalopathy, cerebral calcifications, and cysts: An 8-year neuroimaging follow-up of disease progression and histopathological correlation

Leukoencephalopathy, cerebral calcifications, and cysts (LCC) is an extremely rare neurological disease, also known as Labrune syndrome. The disease more commonly affects children and young adults and the characteristic triple imaging findings are leukoencephalopathy, calcifications and multiple cysts, presenting with a variety of supra- and infratentorial symptoms but lacking for extra-neurological manifestations. Coats plus syndrome and cerebroretinal microangiopathy with calcifications and cysts (CRMCC) share similar neurological findings with LCC, but additionally involves other extra-neurological organs. Tumoral excision is usually required due to mass effect to the eloquent brain of multiple growing cysts or hemorrhages, but the outcome of surgery varies. Here we demonstrate an 8-year neuroimaging study of a rare adult-onset case of LCC with gradual headache, hemiparesis, hand tremors, unstable gait, and seizure attacks despite several times of tumoral excision. Neuroimaging revealed multiple microbleeds and microcalcification in the leukoencephalopathic areas, with increasing calcifications, recurrent previously excised cysts and new cyst formation in the longitudinal neuroimaging follow-ups within the eight years. We believe that LCC involves microangiopathy, which causes blood-brain barrier disruption, myelin serum collection and subsequent growing cysts and dystrophic calcification formation. We provide histopathological correlation in the illustration. Due to the underlying pathomechanism and long-term recurrence nature, patients with a combination of cysts and calcifications on CT scan should be follow up carefully and postoperative recurrence after years may occur.

Longitudinal clinical and neuro-radiological findings in a patient with leukoencephalopathy with brain calcifications and cysts (Labrune syndrome)

Since she was 4 years old, the patient had exhibited frequent convulsive seizures, and she experienced severe headaches and depression in adulthood. At the age of 37 years, cerebral calcifications were detected, but she exhibited no cognitive or motor problems. She suffered a cerebral haemorrhage at 49 years old and experienced cognitive dysfunction, dysarthria, dysphagia, and left-hemiparesis as sequelae. After undergoing gastrostomy, she exhibited very slow cognitive deterioration associated with speech disturbance over more than 10 years. She also gradually developed limb spasticity with Babinski signs. Repeated computerised tomography scans revealed unexpected changes including 2 cysts that appeared separately after small haemorrhages, an intracerebral haemorrhage, and intra-cyst bleeding. These longitudinal scans also showed progressive ventricular dilatation and expansion of the leukoencephalopathy, but there were no apparent changes in the intracranial calcifications. Magnetic resonance imaging revealed numerous microbleeds, and magnetic resonance angiography revealed irregularity of the cerebral artery walls with stoppage. Her SNORD118 gene exhibited compound heteromutation of c.38C > G and c.116G > C on different alleles. She was finally diagnosed with leukoencephalopathy with brain calcifications and cysts (Labrune syndrome) at the age of 61 years. Past reports have suggested that diffuse cerebral microangiopathy underlies Labrune syndrome's pathogenesis, but we speculate that cerebral macroangiopathy may also underlie it.

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Our patient presented with a long history of neurological complaints.

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Computerised tomography scans over many years revealed haemorrhages and cysts.

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She was diagnosed with leukoencephalopathy with brain calcifications and cysts.

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We detected a compound heteromutation in her SNORD118 gene.