The patient was a 79-year-old Japanese man who lived in the southwest part of Japan. He had been undergoing hemodialysis for 4 years due to end-stage diabetic nephropathy. He had been working in a bamboo grove surrounding his house for 4 days just before admission (day − 4 to day − 1). Lightheadedness occurred on day − 1, and the next day, he visited a local clinic (day 0). A blood test showed thrombocytopenia [platelet count of 71,000/μL (normal range 158,000-348,000/μL)] and elevated liver enzymes [aspartate transaminase of 287 U/L (normal range 13–30 U/L) and alanine transaminase of 139 U/L (normal range 10–42 U/L)]. Impaired consciousness occurred, and he was then referred to and admitted to Nagasaki University Hospital on the same day (day 0). On admission (day 0), the patient showed drowsiness with a Japan Coma Scale of II-20 and a Glasgow Coma Scale of 14/15 (E3V5M6). He had a body temperature of 38.4 °C, blood pressure of 141/75 mmHg, pulse rate of 84 beats/min, and respiratory rate of 16 breaths/min. Oxygen saturation was 92% on room air. A swollen tick by blood sucking was attached on the surface of the right precordium. Palpable cervical and inguinal lymph nodes were found on the right side. He had multiple unraised red spots on the left thigh and erythema associated with exfoliation on the groin of both sides. His chest/abdomen examination did not reveal any abnormal findings. Neck stiffness was not apparent. Blood test results from the first examination are shown in Additional file. The hematology test showed pancytopenia, with a white blood cell count of 1800/μL (normal range 3300-8600/μL), hemoglobin of 10.9 g/dL (normal range 13.7–16.8 g/dL), and platelet count of 52,000/μL. Biochemistry tests showed elevation in liver enzymes [aspartate transaminase of 347 U/L, alanine transaminase of 151 U/L, γ-glutamyltransferase of 109 U/L (normal range 13–64 U/L), and lactate dehydrogenase of 878 U/L (normal range 124–222 U/L)]. The serum levels of ferritin and soluble interleukin-2 receptor were 2627 ng/mL (normal range 40–465 ng/mL) and 2135 U/mL (normal range 127–582 U/mL), respectively. Hemophagocytosis was observed in bone marrow aspirates. Blood culture revealed no microorganisms. Right axillary lymphadenopathy was observed in a chest and abdominal radiograph/contrast-enhanced computed tomography (CT) scan. There were no particularly abnormal findings in a noncontrast head CT scan, electrocardiogram, or echocardiograph. On admission (day 0), differential diagnoses included SFTS and rickettsial infections. In accordance with the treatment for severe rickettsial infections, we started infusion of minocycline (200 mg/day) and levofloxacin (500 mg/day) combined with platelet transfusion and recombinant human thrombomodulin administration (8320 U/day). Intravenous immunoglobulin was given as an adjunct therapy. On day 1, unconsciousness rapidly progressed, and a generalized seizure with respiratory failure occurred. His respiration was supported with mechanical ventilation, and systemic management, including continuous hemodiafiltration, was initiated in an intensive care unit. Administration of meropenem (3 g/day) was also started. On day 2, a real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay for SFTSV, which was performed as described previously [], was positive (5.97 log10 copies/mL) in the serum. Furthermore, qRT-PCR for the tick that had bitten the patient was positive (see Additional file ). No Rickettsiaceae, including Orientia tsutsugamushi and Rickettsia japonica, was detected by duplex real-time PCR [] using blood and eschar samples. We administered 200 mg/day hydrocortisone from day 2 considering the possibility of relative adrenal insufficiency. The levels of liver enzymes significantly increased on day 4, and minocycline, levofloxacin and immunoglobulin preparations were discontinued. Because β-D glucan levels increased at 131.1 pg/mL (MK-II assay; negative cutoff value < 20 pg/mL) and both serum Aspergillus and Candida antigen were positive with a value of 4.6 for Aspergillus antigen (negative cutoff index < 0.5), the central venous catheter was replaced, and presumptive therapy with caspofungin 70 mg/day was initiated. After that, serum Cryptococcus antigen was positive (titer; 1:1), and considering the possibility of trichosporonosis, voriconazole 280 mg/day was added to the treatment regimen. On day 5, the serum SFTSV-RNA level reached a peak (9.31 log10 copies/mL) and then decreased. On day 6, severe melena appeared. Lower gastrointestinal endoscopy showed mucous and bloody stool, intestinal edema, and severe rectal hemorrhage. A stool culture detected Candida glabrata. On day 8, β-D glucan levels further increased to 425.5 pg/mL, and a blood culture detected Candida glabrata; therefore, we judged that bacterial translocation occurred from the intestine. Caspofungin and voriconazole were changed to liposomal amphotericin B 250 mg/day, and meropenem was changed to the combination therapy with tazobactam/piperacillin and vancomycin. The levels of liver enzymes peaked on day 8, after which they tended to decrease. After day 12, platelet transfusion became unnecessary. Because impaired consciousness continued even after the sedative was discontinued, encephalopathy was suspected. A lumbar puncture was performed on day 13, and CSF was obtained. The qRT-PCR of CSF to detect SFTSV was positive with a value of 4.10 log10 copies/mL. On day 16, the serum SFTSV-RNA level dropped below the detectable level. On day 31, the patient was discharged from the intensive care unit, and the level of consciousness improved approximately one month after disease onset. There was a swollen right axillary lymph node at the first examination, which remained swollen after viruses disappeared from the blood. However, we could not judge whether SFTSV remained in the lymph node because we did not perform a lymph node biopsy. Although a chest CT scan on admission did not show clear pneumonia findings, infiltrative shadows on the basal area of both lungs were found by a chest CT scan on day 9. In bronchoalveolar lavage fluid (BALF) obtained on day 21, neutrophils were predominant in the cellular fraction, but general types of bacteria were not detected, probably because broad-spectrum antimicrobials had already been administered. However, Cryptococcus antigen (titer; 1:2), Aspergillus antigen (a value of 8.6), and SFTSV-RNA (2.51 log10 copies/mL) were detected, and Aspergillus niger was cultured from the BALF. Therefore, we speculated that fungal pneumonia was induced by transient immunosuppression caused by SFTSV infection and continued liposomal amphotericin B administration. A chest CT scan on day 30 showed that infiltrative shadows were organized overall. Liposomal amphotericin B and tazobactam/piperacillin were discontinued on days 37 and 42, respectively. A slight ground-glass opacity remained, but infiltrative shadows improved on day 51. Although β-D glucan levels remained high and Aspergillus antigen was persistently positive, there was no relapse of aspergillosis or candidemia. SFTSV-RNA was persistently detected in the sputum until day 71 despite its disappearance in the blood on day 16. After confirming that SFTSV-RNA became negative in the sputum on day 127, we stopped performing droplet isolation precautions on the patient.