A 57-year-old female was admitted with pancytopenia, and mild splenomegaly. The multiple myeloma diagnosis was wrongly made since the discovery of monoclonal peak to the protein electrophoresis. Further microscopic examination of bone marrow revealed the accumulation of sea-blue histiocytes. The evolution was stable and the patient did not receive any treatment due to the lack of nervous symptoms.
The syndrome of the sea-blue histiocyte is a rare disorder first described by Silverstein et alin 1970 [
A 57-year-old female was referred to Gastrology department for further examination of anemia. She was the product of consanguineous marriage. It was not similar cases in her family. She had not fever. The hemodynamic parameters were normal. The spleen was slightly palpable. We did not detect any peripheral lymphadenomegaly.
The diagnosis of portal hypertension was referred to the presence of esophageal varicosity grade II to upper gastrointestinal endoscopy with probable liver cirrhosis.
The patient we was addressed for exploration of a spike in serum protein electrophoresis.
The examination was a blood pressure at 14/9 cm Hg; a temperature at 37.3˚, a BMI at 25 kg/m2 and a plenomegaly at 3 cm from the costal margin. Laboratory investigations showed the renal failure with urea at 23.4 mmol/l, creatinine at 186 µmoles/l, Natremia at 136 mg/l, K+ at 4.8 mg/l, Na+ urine = 42 mmol/d; urinary K+ = 34.34 mmol/day; 24 h proteinuria = 0.34 g; Ca++ = 2.29 mg/l, CRP < 5, TP = 82%.
The blood count showed pancytopenia with GB = 2910; PNN = 2000; lymphocytes = 5800, monocytes = 3100; eosinophiles = 10, basophiles = 100; Hb = 8.7 g/dl, MCV = 83.6 fl; MCH = 25.1 pg, reticulocytes = 48,235/ µl, platelets = 54,000/µ.
Electrophoresis of serum protein showed: albumin = 35.8; α1 globulin = 3.5, α2 = 7; β1 = 4.5, β2 = 2.7 and a globulin spike to 20.1 g/l. The blood immunophenotyping was IgG kappa.
The search for urinary light chains was positive with a rate of 31.5 mg/day. The dosage of β2 microglobulin was 10,830 μg/l. The skull radiograph (
Bone marrow biopsy showed a marrow made of wealth between 1 and 2, the seat of histiocytes with abundant cytoplasm vacuolated, the vacuoles are of unequal size, positive PAS staining and Giemsa negative for Perls stain, concluding the diagnosis histiocytosis of “blue sea”. The evolution of our patient was stable by anemic syndrome corrected symptomatically at regular controls.
The sea-blue histiocyte syndrome, similar to NiemannPick disease, is a congenital, hereditary histiolipidosis due to an inborn enzymatic error. Accumulation of non saturated, oxidated, polymerized lipids is observed; ceroids of lipofuscin, glycophospholipids and sphingomyelin, like bulky granules 1 to 3 μ in diameter, turn blue with May Grunewald staining, orange reddish with PAS and black with Sudan III and osmic acid.
The sea-blue histiocytes are preferably located at the bone marrow, liver and spleen and less frequently in
lymph nodes, lungs and some other organs [
In patients with myelofibrosis, extramedullary haematopoiesis commonly occurs in the spleen and liver, but rarely in the lymph nodes [
Within the spleen, which in myelofibrosis functions as an extramedullary hematopoietic organ, monocytes differentiate from hematopoietic stem cells, proliferate, and are transformed into sea-blue histiocytes. Because seablue histiocytes have a large cytoplasm, as do megakaryocytes, it is considered likely that the lungs, and probably the liver, function as a physiological sieve of circulating monocytes, which changed into sea-blue histiocytes in the bone marrow and the spleen, respectively. Moreover, it has been reported that, in a labeling experiment with 3H-thymidine, about 15% and 56% of mice monocytes leaving the circulation become pulmonary macrophages and Kupffer cells, respectively [9-11].
Consequently, a heavy accumulation of sea-blue histiocytes in the spleen of this patient could be explained by these hypotheses. The lysosomal enzyme pathway in macrophages of these disorders results in saturation for removal of the membrane lipid, and the cells are transformed into sea-blue histiocytes [9,10]. The sea-blue histiocytes are usually observed in the bone marrow and spleen, where the majority of the blood cells are destoryed and phagocytosed. On the other hand, Links et al. [
Sea-blue histiocytosis [
Nguyen et al. call attention to a new etiology for seablue histiocytosis and point out that the 149 variant of apoE appears to stimulate cholesterol ester accumulation in macrophages and could be associated with targeting of lipoproteins to macrophages. Splenectomy unmasked the lipoprotein defect and allowed expression of the hyperlipidemia and accumulation of remnant lipoproteins [
The prognosis is variable: fatal in the central nervous system location, relatively mild in cases of spleen and bone marrow location. The possibility of complicating hepatic cirrhosis and/or pulmonary fibrosis is always present [
This case described a primary sea blue histiocytosis which had normal serum triglyceride concentrations. We did not find a particular entity to our patient and her syndrome stay primary. The histology stays of great diagnostic input in this rare entity which stays without a specific treatment.