A 23-year-old North-African woman with no family history of SCD was admitted to our department of internal medicine with symptoms of anemia, bone pain, arthralgia and fever. Her symptoms had been developing for six weeks with alteration of her general condition and abdominal pain. On physical examination our patient was pale, she had a temperature of 39.5°C, her blood pressure was 130/75mmHg and heart rate was 100 beats/minute. The patient had slight splenomegaly, pain on pressure in the long bones and arthritis in her knees.
Blood test results showed normocytic anemia at 6.6g/dL with a high reticulocyte count (230,000 cells/mm3), hyperleukocytosis with granulocytosis (leukocyte count 16,500 cells/mm3, polymorphonuclear cells 9500 cells/mm3) and moderate thrombopenia (100,000 cells/mm3). Further investigations showed diminished haptoglobin (0.08mg/L), elevated lactate dehydrogenase (4670UI/L) indirect hyperbilirubinemia (21mg/L) with moderate cytolysis and cholestasis (aspartate aminotransferase 43U/L, alanine aminotransferase 65U/L, phenylalanine ammonia lyase 217U/L and γ-glutamyl transpeptidase 188U/L). Hemoglobin (Hb) electrophoresis test results showed Hb S at 50.3 percent, Hb C at 44 percent and Hb A1 at 0 percent, confirming a diagnosis of SCD (hemoglobin S/C).
Our patient’s erythrocyte sediment rate was 110mm/first hour, her C-reactive protein level was 38mg/L (range <6mg/L), fibrinogen was 6.4g/L (24g/L) and serum protein electrophoresis showed a polyclonal IgG 24g/L (range 9 to 13g/L) with normal immunofixation. Results of a chest X-ray were normal. Abdominal ultrasonography, transthoracic and transesophageal echocardiography results were also normal. A thoraco-abdominal scan revealed numerous splenic infarctions. The results of a bone scan showed diffuse bone infarcts.
Her symptoms were attributed to SCD and hence our patient received blood transfusions, antibiotics and analgesics, but with no improvement. Her fever and arthritis failed to respond to this treatment. Instead, the evolution of her condition was marked by the development of arthritis in her hands and relapse of anemia.
Blood culture test results were negative, and the result of a tuberculin skin test was an 8mm induration. There was no BK virus found in repeated sputum and urine examinations, and procalcitonin test results were negative.
Serology test results for human immunodeficiency virus, hepatitis B, hepatitis C, brucellosis and typhoid fever were all negative. Cytobacteriological urine analysis revealed no bacteria but microscopic hematuria (670 cells/mm3) and leukocyturia (50 cells/mm3). Proteinuria results were negative.
The results of a Coombs test performed on admission were strongly positive for IgG. Immunological investigations revealed a positive anti-nuclear antibody (1/2600) result, and a positive anti-Sm result. Anti-DNA antibody tests were negative. A test for anti-extractable nuclear antigen antibodies (anti-ENA) was negative. C3 levels and C4 levels were normal (respectively, 0.95g/L and 0.3g/L). Tests for anti-phospholipid antibodies were negative. A diagnosis of SLE associated to SCD was established, with five of the diagnostic criteria of the American College of Rheumatology being met. Steroids were administered as a pulse of methylprednisolone 1g/day for three days followed by oral prednisone at 1mg/kg/day with hydroxychloroquine. Her symptoms quickly improved. At her 18-month follow up, she was in clinical remission on prednisone 5mg per day and hydroxychloroquine; she had not experienced a sickle-cell crisis and her lupus is still quiescent.