Gaucher's disease with uncommon presentations.

Gaucher's disease is the most common lysosomal storage disorder gene defect, which leads to deficiency or decreased activity of glucocerebrosidase, followed by accumulation of glucosylceramide. There is autosomal recessive transmission leading to varied clinical manifestations. This disease has three main types: Type I - nonneuronopathic; type II - acute neuronopathic; and type III - chronic neuronopathic. The nonneuronopathic type has the highest prevalence and also the greatest variability. The authors here report two cases of Gaucher's disease with uncommon presentations in early childhood, highlighting the importance of early diagnosis of the disease, as now-a-days enzyme replacement therapy may arrest further progress of disease.

Introduction

Gaucher's disease is a progressive, debilitating, and some times life threatening disease. Symptoms of Gaucher's disease can appear at any age, often at a very late age. It is the most common lysosomal storage disorder, gene defect leads to deficiency or decreased activity glucocerebrosidase followed by accumulation of glucosylceramide.[1]

This being a genetic disorder and is transmitted from parent to child, both parents must be carriers; the carrier rate in general population is approximately 1 in 100. There is autosomal recessive transmission leading to varied clinical manifestations[2] and may present with various clinical symptoms, often with some uncommon features. Therefore, it is very important to diagnose the disease early so as to give the best treatment and prevent further progress of the disease, as early onset of clinical symptoms and signs predispose patients to severe phenotype with irreversible complications.[3] Here we have reported two cases with unusual presentations—case 1 was nonneuropathic (type 1), which has the highest prevalence and also the greatest variability.[3] The signs and symptoms of type 1 disease demonstrated marked heterogeneity.[4]

Case Reports

Case 1

A one and half years old boy presented with weakness, pallor gradually increasing abdominal girth, and a swelling in the right axilla. There was no neurological manifestation. On examination, there was hepatomegaly and huge splenomegaly. The axillary swelling appeared like an enlarged lymph node, but there was no other nodal enlargement, sternal tenderness was also absent. Blood examination revealed a total leukocyte count of 3,200 cells/m3; a normal differential count; platelets were reduced (1 lakh/m3); hemoglobin was 7.6 gm/dl, abnormal cells were not detected in peripheral blood and liver function test was within normal limits.

Fine needle aspiration cytology (FNAC) was done from the axillary mass and smears showed sheets of mature lymphocytes, immature mononuclear cells and occasional megakarycytes along with few large histiocyte like cells [Figure 1]. The smears were stained with periodic acid Schiff (PAS) and positivity of the histiocyte like cells with PAS stain suggested our diagnosis to be Gaucher's disease with extra medullary hematopoiesis. Bone marrow examination also revealed Gaucher's cells.

Figure 1

Fine needle aspiration cytology from axillary mass showing Gaucher's cells (H and E,×400)

Final confirmation was done by doing the liver biopsy and demonstrating sheets of Gaucher's cells with abundant crumpled tissue paper like cytoplasm. Liver architecture though was normal. Serum acid phosphatase level was high at 45 units/L. Karyotyping was also normal (46XY).

Case 2

A five-year-old boy from Bihar presented with low grade fever, increasing pallor and weakness. On examination, there was moderate hepatosplenomegaly, but no lymphadenopathy. There was no neurological manifestation.

Blood examination revealed a normal picture except that the erythrocyte sedimentation rate (ESR) was very high–108 mm in the first hour.

Bone marrow examination revealed very low cellularity with M:E ratio within normal limits. All cell lines showed normal maturation except erythroid series, which showed partial megaloblastic change and plasma cells were increased. Most important finding was presence of extra and intra cellular Leishmania Donovan (L.D) bodies.

Serological tests were performed, the aldehyde test was positive, rK-39 was also positive, and the patient was diagnosed and treated for Kala Azar.

But even after adequate therapy there was only mild reduction in splenic size. The clinicians advised for bone marrow examination which was repeated. The aspirate was scanty, but there was no LD bodies. A splenic puncture was then performed, the smears from which showed plenty of Gaucher's cells.

Discussion

The type I Gaucher's disease may present in infancy, typically showing anemia, thrombocytopenia, splenomegaly, and bone lesions.

Extramedullary hematopoiesis (EMH) generally occurs in patients with deficient bone marrow hematopoiesis secondary to either peripheral red cell destruction or marrow replacement. EMH is commonly seen in liver and spleen as a diffuse lesion. Rarely EMH presents as a solitary mass posing a diagnostic dilemma.[5]

In the first case we saw the child presenting with axillary mass mimicking lymphadenopathy, but ultimately diagnosed as a case of EMH in Gaucher's disease. EMH is a microscopical finding, but clinically it often can simulate a neoplasm. The megakaryocytes can mimic malignant neoplastic cells. Aspirated smears demonstrate tri lineage hematopoisis and in the present case the authors also found Gaucher's cells in the aspirate.[6]

The second case of Gaucher's disease had another type of pathology, Kala Azar, which masked the typical clinical features. Combination of the dual pathology delayed the diagnosis in this case.

There was no neurological involvement at the time of presentation in both the cases. Splenomegaly was the most important clinical feature in both the cases and pancytopenia in the first one.[7] Although Gaucher's disease is well known in adult patients but about two-thirds of the patients present before the age of 20 and onset in childhood is predictive of severe and progressive phenotype.[8]

The authors have emphasized the early diagnosis high lighting the uncommon presentations so that early treatment by enzyme replacement therapy can be started delaying the complications. However, confirmation for the typing of the cases can only be done by studying the genetic mutations and development of gene therapy (reintroduction of missing DNA sequence) hints the real causal therapy of the disease.[1]