Department of Paediatrics, Asklepios Clinics Sankt Augustin, Germany
Correspondence to: G. Horneff, Department of Paediatrics, Asklepios Clinics Sankt Augustin, Arnold Janssen Str. 29, D-53757 Sankt Augustin, Germany. E-mail: g.horneff{at}asklepios.com
SIR, Autosplenectomy is infrequently described in systemic lupus erythematosus (SLE) [1, 2]. Asplenia is associated with high mortality due to Streptococcus pneumoniae infection [26]. In this case report, we describe a girl who survived pneumococcal sepsis and meningitis. Our observation supports the application of pneumococcal vaccine in SLE patients.
A 15-yr-old girl was treated with prednisolone (5 mg/48 h) and fosinopril due to SLE complicated by nephritis and arterial hypertension. After years of inactive disease she was admitted with fever, headache, cough and tachypnoea.
The diagnosis of SLE was established at the age of 6 yr. Subsequent manifestations included lupus nephritis with nephrotic syndrome, Sjögren's syndrome, pancreatitis, haemolytic anaemia and arterial hypertension. There was no history of anticardiolipin antibodies or thrombosis. Treatment consisted of corticosteroids, methotrexate followed by cyclophosphamide and azathioprine.
The patient was seen 3 months earlier with no clinical manifestations of SLE. At that time the ANA titre was 1:640, antibodies to double-stranded DNA were slightly elevated and complement levels were within the normal range.
On admission, physical examination revealed tachypnoea, a depressed level of consciousness and cold, lilac-livid coloured fingers and toes. There was no stiffness of the neck. The blood pressure was decreased and the girl was anuric. Body temperature was elevated to 38.8°C. The clinical presentation was compatible with sepsis.
Laboratory tests showed thrombocytopenia, leucopenia, neutropenia, highly increased C-reactive protein, elevated creatinine, ASAT and ALAT, as well as abnormal coagulation tests, indicating intravascular coagulation. The ANA titre was 1:640 and antibodies to DNA were 52 U/l (normal range<75 U/l). Antiphospholipid antibodies were undetectable. Complement levels were normal. The blood film showed anisocytosis and HowellJolly bodies. Streptococcus pneumoniae could be cultivated from blood and cerebrospinal liquor.
The chest X-ray showed no infiltration. Computed tomography scanning of the paranasal sinus revealed sinusitis. Fundoscopy was normal, without signs of elevated intracranial pressure. Cerebrospinal fluid opening pressure was not measured.
The spleen was undetectable by ultrasound scan. MRI of the abdomen showed a thin strand of tissue in the area of the spleen (Fig. 1A and B).
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SLE typically involves multiple organ systems. The immune system can show variable abnormalities [7]. It has been suggested that SLE patients demonstrate an increased risk of infection even if they are not treated with immunosuppressants [7]. Possible factors increasing this risk are abnormalities in the complement system, including complement receptors, deficiency of mannose-binding lectin, impaired chemotaxis and phagocytosis of macrophages and polymorphonuclear cells, abnormal T-cell-mediated cytotoxicity, and functional asplenia [7].
The association of functional asplenia and SLE was first described in 1979 [1]. Functional asplenia occurred in approximately 5% of SLE patients [2]. Asplenia may result in impaired elimination of microorganisms and immune complexes and in a decrease in immunoglobulin M serum levels. This leads to increased susceptibility to pneumococcal and salmonella sepsis. The clinical and diagnostic features of this case suggested that sinusitis could have been the starting point of the generalized infection.
HowellJolly bodies, spherocytes and target cells in the red cell population, thrombocytosis and monocytosis are suggestive of splenic dysfunction [3, 4]. The mechanism by which hyposplenism or asplenism develops in SLE is rather unclear. Some authors postulate splenic infarction caused by the antiphospholipid syndrome and thrombosis as a possible mechanism, others suggest vasculitis with silent ischaemia or lymphocyte depletion caused by the presence of a circulating lymphocytotoxin [2, 8, 9].
Fifteen SLE patients with functional asplenia, of whom seven developed sepsis caused by S. pneumoniae (six cases) and by Salmonella species were reported in one review [4]. All were female, aged between 9 and 44 yr, and only two survived. None of them had received pneumococcal vaccination.
Recommendations from the case are as follows: (i) early vaccination with the 23-valent or the pneumococcal conjugate vaccine is mandatory in patients with asplenia; (ii) regular monitoring for HowellJolly bodies is necessary to detect splenic dysfunction; and (iii) adequate anti-infectious prophylaxis in patients with splenic dysfunction is recommended.
The authors have declared no conflicts of interest.
References
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