<i>K. pneumoniae</i> liver abscess following deferoxamine subcutaneous self‐injection
Authors: Ludovico Furlan, Giovanna Graziadei, Giulia Colombo, Laura Virginia Forzenigo, Monica Solbiati
Journal: American Journal of Hematology (2017)

A 47 years old Jehovah's Witness female with non transfusion dependent thalassemia and glucose-6-phoshate dehydrogenase deficiency presented to the Emergency Department (ED) for abdominal pain to the lower quadrants and fever up to 38°C. She reported no cough, dysuria, or diarrhea. Pain was not related to meals or bowel motion. Two weeks before she was successfully treated with oral amoxicillin/clavulanic because of a subcutaneous abscess in the mesogastric abdominal quadrant, at the site of deferoxamine auto-injection. At presentation the patient was febrile, tachycardic, and hypotensive. Physical examination showed short stature and low weight (150 cm, 40 kg), susceptible pain at the upper abdominal quadrants with enlarged and tender liver and spleen. Blood tests revealed an increase in leukocytes (WBC 44 840/mm3), c-reactive protein (27.89 mg/dL, normal value < 0.5), liver enzymes (AST 50 UI/L, ALT 32 UI/L, total bilirubin 6.17 UI/L), and severe anemia (Hb 5.8 g/dL). The abdomen ultrasound scan performed in the ED showed a severely enlarged liver with increased echogenicity but no other significant abnormality. A second ultrasound examination was repeated after 24 h and was remarkable for the presence of a non-homogeneous and prevalently hypoechoic liver lesion. The patients thus underwent CT contrast scan and a subsequent contrast MRI that revealed a multiloculated liver abscess affecting the II, III, and IV hepatic segment (Figure 1, panel A). The lesion appeared to be in communication with the subcutaneous tissue and the skin surface (Figure 1, panel B). Panel A: T2 weighted contrast MRI image showing the hepatic multiloculated abscess affecting the II, III, and IV segment; Panel B: T1 weighted contrast MRI image showing the communication through a fistula (arrow) between the hepatic abscess and the skin surface; Panel C: T2 weighted contrast MRI image showing complete resolution of hepatic abscess after 11 weeks of ceftriaxone therapy Parasites and ova stool test and serology for amoeba were negative. A broad spectrum antibiotic regimen with imipenem, vancomicine, and metronidazole was initially introduced and then switched to ceftriaxone after isolation of Klebsiella pneumoniae on blood cultures. The patient strenuously refused any blood transfusion despite progressive hemoglobin decrease up to 3.5 g/dL. No surgical drainage was performed because of the characteristics of the hepatic lesion and the patient denial to receive blood transfusions. The patient gradually improved and was discharged home after 4 weeks with complete resolution of leukocytosis, normal values of C-reactive protein, and Hb 6.5 g/dL. Antibiotic therapy was continued for 11 weeks overall, until complete resolution of the hepatic abscess at contrast MRI imaging (Figure 1, panel C). Thalassemic patients receiving deferoxamine chelating therapy have been suggested to be at increased risk of Yersinia, Mucomycosis, and Vibrio vulnificus infections due to the similarity of chelating agents with sideropores, specific iron-chelating molecules necessary for fungi and bacteria growth.1-5 To our knowledge, although K. pneumoniae is a well-known cause of hepatic abscess, its prevalence does not seem to be increased by either thalassemia or iron chelating treatment.6 In this case, both the physical characteristics of the patient and the MRI findings suggest that the hepatic abscess might have been the consequence of an initial subcutaneous infection spreading to the liver by the creation of a fistula. This underlines the importance of a correct patients' education when prescribing deferoxamine self-injection. Nothing to report.