A 63-year-old Chinese man presented with the major complaints of abdominal pain and fever for 3 days, in the absence of headache, dizziness, chest pain, dyspnoea, cough and sputum. The highest body temperature was 39.7℃. On physical examination, prominent signs were the urticaria-like skin lesions and the pan-abdominal tenderness. Complete blood count (CBC) showed the following: white blood cells (WBC), 19.13×109/L; neutrophils, 4.55×109/L; monocytes, 8.88×109/L; red blood cells (RBC), 2.38×1012/L; hemoglobin (Hb), 80 g/L; platelets (Plt), 32×109/L; and reticulocytes (Ret), 5.61×109/L, C-reactive protein 142.7 mg/L. Coagulation profile and urine examination did not show any abnormalities. Biochemical analysis reported the elevated serum levels of lactate dehydrogenase (2834 IU/L), hydroxybutyric dehydrogenase (2394 IU/L) and β2-microglobulin (47.3 mg/L), in the absence of abnormalities in liver and renal functions. Pathogenic culture of his blood was sterile. Serologic tests for hepatitis A, B, C virus, and human immunodeficiency virus were negative. Biomarkers of neoplasms were negative too. No positive findings was presented in chest CT. However, abdominal CT scan revealed the swollen small and large intestines, abnormally accumulated airs in his small intestines, and lipotrophic lesions with overt angiogenesis surrounding the unusually thinned and distended small intestines and sigmoid colon, indicating the presence of gut inflammatory lesions (Fig. 1). Morphological examinations showed a heavily hypercellular bone marrow, with the significantly increased percentages of monoblasts (accounting for 44.5% of the total nucleated hematopoietic cells) and premonocytes (accounting for 24.5%). Increased percentages of premonocytes (44%) and monocytes (46%) were present on the blood smears (Fig. 2). Cytogenetic analysis reported a karyotype of 48,XY,t(8;21)(q22;q22),+13,+13[9]/49,idem,+mar[9]/49,idem,+8[2] (Fig. 3). Molecular biological analysis revealed the presence of a mutated FLT3-TKD gene and a fused AML1–ETO gene. Two groups of abnormal myeloid precursors were detected by flow cytometry. One group (accounting for 32.53% of the total nucleated cells) expressed CD13, CD33, CD14, CD11b, CD36, CD56, CD64, CD123 and HLA-DR; another group (accounting for 48.95% of the total nucleated cells) expressed CD34, CD117, CD38, HLA-DR, CD13, CD33, CD11b, CD56 and CD123. These data fulfilled the diagnostic criteria for AML-M4 with t(8;21)(q22;q22)/RUNX1-RUNX1T1 [1].
After admission, He was treated with piperacillin-tazobactam and etimicin for his febrile disease and dexamethasone for his urticaria-like skin lesions. He was also prescribed polyglycol electrolyte solution (1500 ml daily for 2 days) followed by rifaximin (200 mg four times daily) and berberine (0.3 g thrice times daily) in an attempt to quickly get rid of the pathogens and their metabolites in the intestines.The febrile episode and the urticaria-like skin lesions were quickly resolved. Surprisingly, the hematological profile gradually improved (CBC results in the following time are outlined in Fig. 4). On day 31, CBC showed the following: WBC, 10.83×109/L; neutrophils, 6.24×109/L; monocytes, 1.62×109/L; RBC, 2.74×1012/L; Hb, 93 g/L; Plt, 253×109/L; and Ret, 112.45×109/L. The absence of leukemia cells on blood smears indicated the loss of clonal growth advantage and an achievement of clinical hematological remission. He refused chemotherapy and hypomethylation therapy and was released. on day 51, he was admitted with the same symptoms as he was first admitted to our center. CBC and morphological examination of the blood smears confirmed the disease recurrence. Repeating the abovementioned treatment resulted in the second clinical and hematological responses. On day 105, he experienced the second recurrence, demonstrated resistance to antibiotic treatment and died of septic shock at another hospital.