MATERIALS AND METHODS

Le Infezioni in Medicina, n. 2, 117-122, 2016 ORIGINAL ARTICLE 117 An analysis of children with brucellosis associated with haemophagocytic lymphohistiocytosis Kamuran Karaman 1, Sinan Akbayram 1, Sultan Kaba 2, Serap Karaman 2, Mesut Garipardıç 1, İlyas Aydın 2, Ahmet Fayik Öner 1 1 Department of Pediatric Hematology, Yuzuncu Yil University, Van, Turkey; 2 Department of Pediatrics, Yuzuncu Yil University, Van, Turkey SummaRY This retrospective study included seven paediatric cases aged from 4 to 14 (10.2±3.4) years with pathologically proved haemophagocytic lymphohistiocytosis from a single institution during 2009 and 2013. Over this time period, 496 patients with brucellosis were diagnosed. None of the patients (3 boys and 4 girls) had a history of any haematologic disorder. All patients had an anamnesis for recently consumed unpasteurised homemade dairy products or had a contact history with sheep and/ or cows. The diagnosis of brucellosis was confirmed by standard tube agglutination test in all patients; titres were 1: 1280 in seven patients. Blood culture was positive for Brucella melitensis in three patients (42%). Bone marrow cultures were positive for B. melitensis in four patients (57%). Fever was present in all patients (100%) with haemophagocytic lymphohistiocytosis. The other most common symptoms were malaise, myalgia, anorexia, sweating and weight loss. In addition, sweating was observed in five patients, and lymphadenopathy, petechiae, and weight loss were observed in one patient. Hepatomegaly, splenomegaly, and hepatosplenomegaly were found in four (57%), six (85%) and four (57%), patients, respectively. Haemophagocytosis was documented in bone marrow examinations of all children except in two cases. All patients recovered completely, and their peripheral blood counts returned to normal by 2 to 4 weeks after antibiotic treatment of brucellosis. Keywords: brucellosis, childhood, haemophagocytic lymphohistiocytosis (HLH), pancytopenia. Corresponding author Kamuran Karaman E-mail: kamuran_karaman@hotmail.com n INTRODUCTION Haemophagocytic lymphohistiocytosis (HLH) is a fatal condition of severe hyperinflammation that results from an uncontrolled proliferation of activated lymphocytes and histiocytes secreting high amounts of inflammatory cytokines. HLH is classified into two major groups as genetic (primary) and acquired (secondary) [1]. Both of cases of HLH are often precipitated by acute infection [2]. HLH is a distinct clinical entity characterized by fever, pancytopenia, splenomegaly, and haemophagocytosis in bone marrow, liver, or lymph nodes. HLH may be diagnosed in association with autoimmune diseases, genetic, malignant, metabolic, collagen vascular and infectious disease such as brucellosis, miliary tuberculosis, Epstein-Barr virus, Cytomegalovirus, Parvovirus B19, human immunodeficiency virus, and some fungal infections [3]. In recent years, many more cases of infection associated haemophagocytic disorders have been diagnosed, brucellosis is one of the rare causes of HLH. The aim of this study was to evaluate the clinical and laboratory findings and management of children with brucellosis associated with HLH. n MATERIALS AND METHODS In this study, medical chart records of children with brucellosis aged under or equal to 18 years who admitted to Yuzuncu Yil University Medical

118 K. Karaman, et al. Faculty Hospital between January 2009 and December 2013 were analyzed retrospectively. Over this time period, 496 patients with brucellosis were diagnosed. Patients known to have any acute or chronic systemic disease other than brucellosis were excluded from the study. In addition to personal/family history and physical examination, complete blood count, triglycerides, fibrinogen, ferritin, alanine aminotransferase, aspartate aminotransferase, bilirubin, lactate dehydrogenase, sodium, blood urea nitrogen, creatinine, serology, bone marrow aspiration for documentation of haemophagocytosis, brucella blood and bone marrow cultures of all children were analyzed. Over this time period, seven children were diagnosed as having HLH associated with brucellosis in our hospital. The diagnosis of brucellosis was made based on a compatible clinical picture with brucellosis together with positive brucella agglutination titers (1:160 or higher titers) or isolation of brucella from blood, bone marrow, or both. The diagnosis of HLH was made according to the guidelines of the Histiocyte Society. The Histiocyte Society has developed a set of diagnostic guidelines that encompass both clinical and laboratory findings [4, 5]. With additional experience these diagnostic criteria have been modestly modified, as shown in Table 1. In this Table 1 - Diagnostic Criteria of Haemophagocytic Lympho histiocytosis (HLH)*. 1. Molecular diagnosis of haemophagocytic lymphohistiocytosis (HLH) or X-linked lymphoproliferative syndrome (XLP). 2. Or at least 3 of 4: a. Fever b. Splenomegaly c. Cytopenias (minimum 2 cell lines reduced, haemoglobin levels <9 g/dl, platelets <100 109 /L, neutrophils <1.0 109 /L) d. Hepatitis 3. And at least 1 of 4: a. Haemophagocytosis b. Ferritin (Ferritin >500 µg/l) c. sil2rα (age based) d. Absent or very decreased NK function 4. Other results supportive of HLH diagnosis: a. Hypertriglyceridemia (Fasting triglycerides 265 mg/dl) b. Hypofibrinogenemia (Fibrinogen 1.5 g/l) c. Hyponatremia * shows the reference for diagnostic criteria: Filipovich AH, 2009 [4) Figure 1 - Presence of haemophagocytes in bone marrow aspiration. study, the criteria for case inclusion were based on clinical and pathologic findings of bone marrow samples revealing haemophagocytosis. In order to exclude malignancy as a cause of pancytopenia, bone marrow aspiration was performed, which showed the presence of haemophagocytes (Figure 1). The medical records of the patients were reviewed. Details of presentation, diagnosis, treatment and outcomes were analyzed. No genetic analyses were done for HLH. The treatment of brucellosis was carried out with preferred antibiotic regimen which consisted of a combination of doxycycline and rifampicin (in children older than 8 years) or co-trimoxazole and rifampicin (in children younger than 8 years) for 6 to 8 weeks. Patients were periodically followed for clinical and laboratory findings. n RESULTS The study included 4 boys and 3 girls patients aging from 4 to 14 (10.2±3.4) years. None of the patients had a history of any haematologic disorder. All patients had an anamnesis for recently consumed unpasteurized homemade dairy products or had a contact history with sheep and/or cows. It is well-known that brucellosis occurs much more often in rural areas. The time elapsed between the presumed exposure and the

An analysis of children with brucellosis associated with haemophagocytic lymphohistiocytosis 119 Table 2 - Clinical findings in brucellosis associated with HLH. Features of patients n (%) Age at diagnosis, mean±sd (years) (10, 2±3, 4) Gender (F/M) Male 4 (57) Female 3 (43) Symptoms Myalgia 4 (57) Anorexia 3 (43) Fever 100 (100) Fatigue 2 (28) Abdominal pain 2 (28) Sweating 5 (71) Headache 2 (28) Signs Splenomegaly at diagnosis 6 (85) Hepatomegaly at diagnosis 4 (57) Arthritis 1 (14) Weight loss 1 (14) Petechiae 1 (14) Hepatosplenomegaly at diagnosis 4 (57) Lymphadenopathy 1 (14) onset of illness could not be ascertained in our patients. Serological tests performed for Epstein-Barr virus which is the most common cause of infectious related HLH, Cytomegalovirus, and Salmonella were all negative. The diagnosis of brucellosis was confirmed by standard tube agglutination test in all patients; titers were 1:1280 in 7 patients. Blood culture was positive for Brucella melitensis in 3 patients (42%). Bone marrow cultures were positive for Brucella melitensis in 4 patients (57%). Clinical findings of the 7 patients are presented in Table 2. Fever was present in all of the patients (100%) with HLH. The other most common symptoms were malaise, myalgia, anorexia, sweating, and weight loss. In addition, sweating was observed in 5 patients, and lymphadenopathy, petechial, and weight loss were observed in 1 patient. Hepatomegaly, splenomegaly, and hepatosplenomegaly were found in 4 (57%), 6 (85%), and 4 (57%), patients, respectively. The laboratory findings of the patients on the first day are shown in Table 3. Thrombocytopenia, neutropenia, hepatitis, hyponatremia, and hyperferritinemia were found in all patients Table 3 - Results of some laboratory manifestations in 7 patients with brucellosis associated with HLH with patient no and on the first day of admission laboratory findings. 1 2 3 4 5 6 7 Haemoglobin g/dl 7.2 11 10.6 8.2 10.8 8 12 Neutrophil count (cell/mm 3 ) 800 900 600 530 400 700 600 Platelet count (cell/mm 3 ) 9,000 77,000 22,000 39,000 82,000 18,000 60,000 Triglycerides mg/dl 208 267 318 221 309 488 363 Fibrinogen mg/dl 41 340 15 147 230 76 86 Ferritin ng/ml 17429 856 1952 4050 6700 4500 6940 Alanine aminotransferase U/L 133 38 46 71 55 94 363 Aspartate aminotransferase U/L 656 14 108 181 110 343 923 Bilirubin mg/dl 2.6 0.7 1.5 0.9 1.3 3.1 2.8 Lactatdehidrogenase U/L 1744 528 669 1773 1181 1277 2952 Sodium mmol/l 127 128 126 128 128 121 129 Blood urea nitrogen mg/dl 16 7 9 14 11 13.1 11 Creatinine mg/dl 0.6 0.2 0.5 0.6 0.4 0.3 0.5 Blood culture (Brucella melitensis) + + - - - + - Bone marrow culture (Brucella + + + - - + - melitensis) Haemophagocytosis in bone marrow - + + + - + + Standard tube agglutination (titer) 1/1280 1/1280 1/1280 1/1280 1/1280 1/1280 1/1280

120 K. Karaman, et al. Table 4 - Laboratory data on the 14th day of treatment. 1 2 3 4 5 6 7 Haemoglobin g/dl 8.4 11 9.8 10.8 11.9 9.6 11.3 Neutrophil count (cell/mm 3 ) 2600 1000 2600 2200 2000 1550 1600 Platelet count (cell/mm 3 ) 535,000 263,000 258,000 138,000 82,000 122,000 110,000 Triglycerides mg/dl 138 183 206 222 209 165 125 Fibrinogen mg/dl 453 240 121 307 232 256 350 Ferritin ng/ml 254 287 340 1357 1100 610 580 Alanine aminotransferase U/L 15 30 20 32 45 35 39 Aspartate aminotransferase U/L 21 49 32 29 62 48 37 Bilirubin mg/dl 1.1 0.4 0.8 0.7 0.8 1 0.8 Lactatdehidrogenase U/L 254 335 253 481 385 409 357 Sodium mmol/l 137 135 131 135 138 143 132 Blood urea nitrogen mg/dl 13 10 11 12 9 12 11 Creatinine mg/dl 0.6 0.4 0.5 0.6 0.4 0.3 0.5 (100%). Hypertriglyceridemia was detected in 5 patients (71%). Pancytopenia was found in 3 patients (42%). Anemia was detected in 3 patients (42%). Hypofibrinogenemia was observed in 4 patients (57%). Splenomegaly was found in 5 (71%) patients. Haemophagocytosis was documented in bone marrow examinations of all children except two cases. All patients recovered completely, and their peripheral blood counts returned to normal by 2 to 4 weeks after antibiotic treatment of brucellosis. In Table 4 are reported the laboratory findings on the 14 th day (follow-up). n DISCUSSION HLH is a fatal and likely underdiagnosed disease characterized by a hyperinflammatory condition caused by increased levels of circulating inflammatory cytokines due to a highly stimulated but ineffective immune process [6-8]. HLH represents a severe hyperinflammatory condition, the cardinal symptoms being prolonged fever, cytopenias, hepatosplenomegaly, and haemophagocytosis by activated, morphologically benign macrophages. Biochaemical markers include elevated ferritin and triglycerides, and low fibrinogen. Acquired HLH is not associated with any known genetic abnormality or immunodeficiency syndrome. Reactive or secondary HLH occurs in the setting of viral, bacterial, fungal, parasitic infection or underlying rheumatologic disorders or malignancy [9-11]. Brucellosis remains an important public health problem in Turkey and can affect people at any age group, including children, representing 20% to 25% of cases [12]. In most of the children with brucellosis, an isolated bacterium is Brucella melitensis, which is endemic in Turkey [13]. In our patients, blood culture was positive for Brucella melitensis in 3 patients and bone marrow cultures was positive for Brucella melitensis in 4 patients. Haematologic complications of mild anemia and leukopenia have been frequently associated with acute brucellosis, but pancytopenia is less frequently seen [14]. The diagnosis of brucellosis was confirmed by standard tube agglutination test in all patients; titers were 1:1280 in 7 patients. In addition, granulomatous bone marrow lesions and haemophagocytosis in the bone marrow are thought to be the other causes for pancytopenia [15]. The exact mechanism of the induction of haemophagocytosis in reactive histiocytic proliferation, as in the case of brucellosis are unclear. Haemophagocytosis results from uncontrolled T-lymphocyte activation that promote macrophage activation and huge amounts of cytokine secretion such as interferon-γ (IFN-γ), tumor necrosis factor alpha (TNF-α), interleukin (IL)-1, and IL-6 [11]. The incidence of bacterial-associated HLH varies between studies [16,17]. Brucella associated

An analysis of children with brucellosis associated with haemophagocytic lymphohistiocytosis 121 HLH is reported as a rare infectious agent in those studies. In a study by Martin-Moreno et al. stated that 5 cases of HLH out of 42 cases of brucellosis and they suggested that brucellosis must be considered as a possible diagnosis among patients with a clinical features of haemophagocytosis especially in endemic regions where brucella infection is common [18]. Karakukcu et al. described 8 patients with pancytopenia within 54 cases of brucellosis and they found 3 patients with haemophgocytosis out of those 8 patients [19]. They stated that pancytopenia and haemophagocytosis were transient and recovered in all patients upon appropriate antibiotics treatment. In another study, the haematological manifestations of 233 brucellosis cases were discussed; pancytopenia and mild to moderate haemophagocytosis on the bone marrow smear were detected in 8% of the cases [20]. Haemophagocytosis in Brucella infection has been described by Erduran et al. in an 8 year-old male patient [21]. Akbayram et al., described 25 patients with pancytopenia and haemophagocytosis was observed in the bone marrow of 3 patients [22]. Herein, we reported seven cases of brucellosis-associated HLH as the largest pediatric series in the literature. In our study, all patients recovered completely and their peripheral blood counts returned to normal by 2 to 4 weeks after antibiotic treatment of brucellosis. In conclusion, brucella infection associated with HLH was reported rarely in literature; however, due to the high incidence of brucellosis in our country, brucellosis should be considered in those patients with prolonged fever, cytopenias, hepatosplenomegaly, elevated ferritin and triglycerides, and low fibrinogen as associated with HLH. Our findings indicated that, although HLH has high mortality rate, it can be seen in case of brucellosis and can be treated completely with appropriate antibiotic regimens. So brucella infection should be kept in mind for etiologic investigation of HLH. Declaration of interest statement: The authors have no conflicts of interest to declare. n REFERENCES [1] Janka G.E. Hemophagocytic syndromes. Blood Rev. 21, 245-253, 2007. [2] Pradalier A., Teillet F., Molitor J.L., Drappier J.C. Macrophage activation syndrome, hemophagocytic syndrome. Pathol. Biol. 52, 407-414, 2004. [3] Dilber E., Erduran E., Kalyoncu M., Aynaci F.M., Okten A., Ahmetoglu A. Hemophagocytic syndrome as an initial presentation of miliary tuberculosis without pulmonary findings. Scand. J. Infect. Dis. 34, 689-692, 2002. [4] Filipovich A.H. Hemophagocytic lympho histiocytosis (HLH) and related disorders. Hematol. Am. Soc. Hematol. Educ. Prog.127-131, 2009. [5] Henter J.I., Horne A., Arico M., et al. HLH-2004: diagnostic and therapeutic guidelines for hemophagocytic lympho histiocytosis. Pediatr. Blood Cancer 48, 124-131, 2007. [6] Vaiselbuh S.R., Bryceson Y.T., Allen C.E., Whitlock J.A., Abla O. Updates on histiocytic disorders. Pediatr. Blood Cancer. 61, 1329-1335, 2014. [7] Usmani G.N., Woda B.A., Newburger P.E. Advances in understanding the pathogenesis of HLH. Br. J. Haematol. 161, 609-622, 2013. [8] Mehta R.S., Smith R.E. Hemophagocytic lympho histiocytosis (HLH): a review of literature. Med. Oncol. 30, 4, 740, 2013. [9] Bay A., Bosnak V., Leblebisatan G., Yavuz S., Yilmaz F., Hizli S. Hemophagocytic lympho histiocytosis in 2 pediatric patients secondary to hepatitis A virus infection. Pediatr. Hematol. Oncol. 29, 211-214, 2012. [10] Onishi R., Namiuchi S. Hemophagocytic syndrome in a patient with rheumatoid arthritis. Intern. Med. 33, 607-611, 2014. [11] Yao M., Cheng A., Su I. Clinicopathological spectrum of haemophagocytic syndrome in Epstein-Barr virus associated peripheral T-cell lymphoma. Br. J. Haematol. 87, 535-543, 1994. [12] Akbayram S., Dogan M., Peker E., Akgun C., Oner A.F., Caksen H. Thrombotic thrombocytopenic purpura in a case of brucellosis. Clin. Appl. Thromb. Hemost. 17, 245-247,2011. [13] Mantur B.G., Akki A.S., Mangalgi S.S., Patil S.V., Gobbur R.H., Peerapur BV. Childhood brucellosis a microbiological, epidemiological and clinical study. J. Trop. Pediatr. 50, 153-157, 2004. [14] Citak E.C., Citak F.E., Tanyeri B., Arman D. Hematologic manifestations of brucellosis in children: 5 years experience of an Anatolian center. J. Pediatr. Hematol. Oncol. 32, 137-140, 2011. [15] Al-Eissa Y., Al-Nasser M. Haematological manifestations of child-hood brucellosis. Infection. 21, 23-26, 1993. [16] Sailler L., Duchayne E., Marchou B., et al. Etiological aspects of reactive hemophagocytoses: retrospective

122 K. Karaman, et al. study in 99 patients [in French]. Rev. Med. Interne. 18, 855-864, 1997. [17] Janka G., Imashuku S., Elinder G., Schneider M., Henter J.I. Infection and malignancy associated hemophagocytic syndromes: secondary hemophagocytic lympho histiocytosis. Hematol. Oncol. Clin. North Am. 12, 435-444, 1998. [18] Martin-Moreno S., Soto-Guzman O., Bernaldo-de-Quiros J., Reverte-Cejudo D., Bascones-Casas C. Pancytopenia due to hemophagocytosis in patients with brucellosis: a report of four cases. J. Infect. Dis. 147, 455-459, 1983. [19] Karakukcu M., Patiroglu T., Ozdemir M.A., Gunes T., Gumus H., Karakukcu C. Pancytopenia, a rare hematologic manifestation of brucellosis in children. J. Pediatr. Hematol. Oncol. 26, 803-806, 2004. [20] Akdeniz H., Irmak H., Seçkinli T., Buzgan T., Demiröz A.P. Hematological manifestations in brucellosis cases in Turkey. Acta Med. Okayama. 52, 63-65, 1998. [21] Erdurana E., Makuloglub M., Mutlub M. A rare hematological manifestation of brucellosis: reactive hemophagocytic syndrome. J. Microbiol. Immunol. Infect. 43, 2, 159-162, 2010. [22] Akbayram S., Dogan M., Akgun C., et al. An analysis of children with brucellosis associated with pancytopenia. Pediatr. Hematol. Oncol. 28, 203-208, 2011.