Isolated Neurosarcoidosis Revealed by Diabetes Insipidus, Visual Loss and Diplopia in a Child Patient: A Diagnostic Problem

Abstract

We report a case of 15-yr-old child that was presented with headache, polyuria, polydipsia, recent ocular motor and abducens nerve palsies and rapid visual loss. He had a long history of progressive symmetric muscular weakness predominant in the lower limb girdle. Water deprivation revealed central diabetes insipidus. Hormonal explorations demonstrated preserved pituitary function with mild hyperprolactinemia at 21.5 ng/ml (N: 2.6 to 13.1 ng/ml). Magnetic resonance imaging showed an extensive isosignal T1 and hyposignal T2 enhanced lesion infiltrating the pituitary gland, optic-chiasmal hypothalamic region, cavernous sinus, cerebrum tent and sphenoid and temporal meningeal spaces. The serum level of angiotensin converting enzyme and cerebrospinal fluid analysis were normal. No other systemic localisation was identified. Muscle biopsy objectified dystrophic changes. Genetic study identified a delT 521 mutation characteristic of Limb-girdle muscular dystrophy type 2C. Corticotherapy rapidly ameliorated the neurological symptoms. This patient was diagnosed as having neurosarcoidosis. Neurosarcoidosis is rarely reported in childhood. We discuss the problems related to diagnosis in such a situation below.

Magnetic resonance imaging and symptoms in patients with neurosarcoidosis and central diabetes insipidus

“…The mean duration from disease onset to diagnosis was 3.4 months. Isolated neurosarcoidosis was reported in four patients [7,8,10,12]. Brain MRI showed abnormal findings in the pituitary stalk in 10 patients [7,8,[10][11][12][13]16], abnormal findings in the pituitary gland in nine patients [8][9][10][11][12][13]15], and loss of high intensity of the posterior lobe of the pituitary in nine patients [8,9,[11][12][13].…”

“…The patients included 12 men [8-12, 14, 15, 17] and eight women [7,10,13,16,18,19], with a mean age of 33 years. The first symptom was polyuria in 13 patients [7][8][9][11][12][13][14][15][16][17] and polydipsia in eight patients [7][8][9][11][12][13][14][15]. The mean duration from disease onset to diagnosis was 3.4 months.…”

“…Isolated neurosarcoidosis was reported in four patients [7,8,10,12]. Brain MRI showed abnormal findings in the pituitary stalk in 10 patients [7,8,[10][11][12][13]16], abnormal findings in the pituitary gland in nine patients [8][9][10][11][12][13]15], and loss of high intensity of the posterior lobe of the pituitary in nine patients [8,9,[11][12][13]. Twelve patients were diagnosed through biopsies of the lymph nodes [8,10,14,16,17], lungs [8][9][10], and skin [13,15], while only one patient underwent a brain biopsy [8].…”

“…Steroid therapy was administered to 17 patients [8][9][10][11][12][14][15][16][17][18][19], infliximab was administered to two patients [17,19], cyclophosphamide was administered to one patient [10], and methotrexate was administered to one patient [19]. Desmopressin (1-desamino-8-D-arginine vasopressin) (DDAVP) was used to treat the symptoms of CDI in 19 patients [7][8][9][10][11][12][13][14][16][17][18][19]. Fourteen patients showed improvement in their abnormal brain MRI findings [8][9][10][11][12][13][15][16][17], but no patients showed improvement in the loss of high signal intensity in the posterior lobe of the pituitary.…”

Management of diabetes insipidus and adipsia in the child

“…Spontaneous evolution of thick pituitary stalk was similar in both reports from unchanged (30%), to reduction (30e50%) or further enlargement (10e20%). In case of pituitary stalk thickness, germinoma or LCH should be ruledeout although other exceptional conditions such as neurosarcoidosis or granulomatosis with polyangiitis, might be the underlying cause [66,67]. Attention should be paid for LCH as long-term unfavorable outcomes associated with bone or lung involvement are highly suggestive of primary pituitary stalk-related LCH leading to CDI [9], and raises an argument about a possible relationship between idiopathic CDI and single central nervous system target of LCH.…”