Case presentation
A 68-year-old Japanese man (height 171 cm, weight 78 kg) with no
background of immunosuppression presented to the Outpatient Department
of Juntendo University Hospital (1,051-bed university-affiliated
hospital), in Tokyo, Japan, complaining of weakness in the lower limbs,
slurred speech, and lower back pain. The patient had a medical history
of chronic atrial fibrillation, and hypertension, for which had been
treated with rivaroxaban and calcium channel blockers. On examination,
he was conscious, his body temperature was 36.9 ℃, blood pressure was
74/59 mmHg, heart rate was 116 beats/minute, and respiratory rate was
17/minute. Oxygen saturation was 97% on room air. Diffuse muscle
tenderness was noted in all four extremities (manual muscle test was
4/5), with numbness in the right upper and lower limbs. Initial
laboratory findings revealed a leukocyte count of
10.4x109/L (normal range of 3.9x109- 9.7x109/L), hemoglobin of 16.5 g/dL, platelet count
of 58x109/L, creatinine of 2.88 mg/dL, and C-reactive
protein (CRP) of 27.97 mg/dL. The creatinine kinase (CK) level was
significantly elevated to 37370 U/L, and the blood myoglobin level was
11850 ng/mL. His urine was reddish-brown in color, but culture test was
negative. Considering his renal function (estimated glomerular
filtration rate of 18.2), and risk of contrast material-induced
nephrotoxicity [2], a non-contrast computed tomography (CT) scan was
conducted. An abdominal CT revealed a 26-mm-diameter hypodense lesion in
the right lobe of the liver (Fig. 1). Chest X-ray and CT showed no
abnormality. Based on all the findings, the patient was diagnosed with
rhabdomyolysis and was immediately started on hydration at 3000 ml/day.
He was admitted to the general ward. His serum CK level decreased to
24637 U/L, and his creatinine level to 1.9 mg/dL at 9 hours after
admission.
On the 3rd hospital day, the patient developed
respiratory insufficiency and was transferred to our intensive care unit
(ICU). Because of hypoxemia, he was intubated, and mechanical
ventilation was started. Arterial blood gas showed metabolic acidosis
and hypoxemia (pH 7.30, pCO2 45 mmHg,
pO2 84 mmHg, HCO3- 22.4 mmol/L,
lactate 3.2 mmol/L, under FiO2 0.8). Another CT scan
revealed multiple newly emerged inflammatory infiltration shadows in the
lung and enlarging hypodense lesions in the liver compared to that on
admission (Fig. 2). Newly emerged retropharyngeal abscesses and psoas
major abscesses were also detected (Fig. 3). Therefore, two sets of
blood cultures and urine cultures were performed, and intravenous
meropenem (6 g/day) and vancomycin (2 g/day) as well as other supportive
treatments were started immediately. On the 4th day,
laboratory findings revealed a leukocyte count of
12.7x109/L, platelet count of
24x109/L, CRP of 34.63 mg/dL, and procalcitonin (PCT)
of 29 ng/mL. His body temperature increased to 40.1℃. Based on his
rapidly deteriorating general status and hypotension requiring
crystalloid infusion and vasopressors (norepinephrine 0.1 µ/kg/min and
vasopressin 0.03 U/min), he was diagnosed with septic shock. Both blood
and urine cultures showed hvKP with a positive string test. To adsorb
endotoxin, polymyxin B-immobilized fiber column direct hemoperfusion
(PMX-DHP) treatment was performed for twice (18 hours and 18.5 hours,
respectively). Due to such intensive care, he recovered from septic
shock, vasopressors were discontinued, and pulmonary oxygenation
(PaO2/FiO2) improved to 234 mmHg after
PMX-DHP treatment. Vancomycin was stopped on the 9thhospital day.
Although his general status improved, inflammation due to the multiple
abscesses was prolonged. As the liver abscess was too small and the risk
with percutaneous drainage at first outweighed the benefit, the abscess
gradually became enlarged (Fig. 4). On the 12thhospital day, ultrasonic-guided percutaneous drainage of the liver
abscess was carried out. Twenty-five milliliters of pus was drained; the
catheter placed was indwelling. Stab culture of the liver abscesses also
revealed Klebsiella pneumoniae . On the 18thhospital day, drainage of the retropharyngeal abscess and tracheostomy
were conducted, and he was weaned from mechanical ventilation. Finally,
his CK level dropped to normal on the 22nd hospital
day. Because inflammatory mediators remained high, percutaneous drainage
of the psoas major abscess was performed guided by CT scan on the
28th hospital day. After this drainage, his condition
gradually improved, even though meropenem was administered for almost 2
months. He was discharged from the ICU to the general ward on the
33rd hospital day. His physiotherapy rehabilitation
continued for 3 months, and he was transferred to a rehabilitation
hospital on the 142nd hospital day.