The Indian Journal of Pediatrics | 2019
Child with Progressive Hemiparesis: Think Beyond Neoplastic Disorders- Correspondence
Abstract
To the Editor: I have read with great interest the article entitled BChild with progressive hemiparesis: think beyond neoplastic disorders^ by Sharawat et al. published recently [1]. In the index case the child developed deterioration of motor skills involving right upper and lower limbs and speech abnormality indicating regression of previously achieved normal development, which was also progressive in character. The child did not have any symptom suggestive of raised intracranial pressure (RIP), papilledema or false localising signs of brain neoplasm. Therefore, in the face of regression of milestones of progressive nature without clinical evidence of RIP, provisional diagnosis of degenerative brain disease (DBD) should appear instead of intracranial space occupying lesion which the author has considered. In view of absence of seizures, hearing or visual impairments, intellectual deterioration and presence of spasticity and bilateral pyramidal signs in the early part of illness, speaks more in favour of white matter degenerative disease or leukodystrophy than gray matter degenerative disease. For DBD consideration, cerebrospinal fluid study which may reveal raised protein content with normal sugar and cell count, could have been done. The magnetic resonance imaging (MRI) of brain helps to distinguish between intracranial mass lesions like brain neoplasm, and DBD. Patients with childhood cerebral adrenoleukodystrophy (CCALD) or adolescent adrenoleukodystrophy show cerebral white matter lesions that are characteristic with respect to location and attenuation patterns on MRI. In 80% of patients, the lesions are symmetric and involve the periventricular white matter in the posterior parietal and occipital lobes [2]. Asymmetrical white matter signal changes were atypical in the present case. Abnormal white matter signal is often seen in splenium or genu of the corpus callosum which was also seen in this case. Other leucodystrophies or multiple sclerosis may mimic these radiographic findings. The author has confirmed the diagnosis of X-linked adrenoleukodystrophy (X-ALD) by genetic testing which may not be available in all healthcare facilities. The neurodegenerative disease often is neurometabolic, but neurometabolic disease is not always degenerative [3]. So, metabolic screening is not infrequently warranted in DBD cases. Definitive diagnosis depends on demonstration of high level of plasma Very long chain fatty acid (VLCFA), which occurs only in X-ALD and other peroxisomal disorders and thus helps to distinguish from other leukodystrophies [2]. Cerebral forms of ALD may present as RIP and unilateral mass lesions. These cases only may be mistakenly diagnosed as brain tumors [2]. Patients with X-ALD are asymptomatic at birth [4]. Almost all males with X-ALD develop adrenocortical insufficiency during life, about 80% before adulthood [5]. More than 85% of patients with CCALD have elevated levels of ACTH in plasma and impaired cortisol response to intravenous ACTH. Therefore, these patients should be evaluated by estimation of plasma ACTH, basal cortisol and its level following ACTH administration to find out any evidence of adrenal insufficiency. Though in the present case the author has confirmed the diagnosis by genetic analysis of ABCD1 gene, it is suggested that examination of cerebrospinal fluid, estimation of plasma VLCFA, cortisol and ACTH also might be helpful to arrive at the diagnosis of X-ALD where facilities for mutational analysis is unavailable and when provisional diagnosis of DBD, specially leukodystrophy is suspected by clinical examination and MRI brain abnormality.