A 27-year-old female was admitted to the hospital on January 26, 2022, with the chief complaints of fever, chest tightness, and shortness of breath for seven days, which exacerbated for four days. Seven days before her admission to our hospital, she started to develop fever and chills without any obvious cause. Her highest temperature was 38.6°C. In addition, she also had chest tightness and shortness of breath, profuse sweating, a maximum heart rate of 150 beats/min. Later on, she started to have a productive cough with a small amount of gray and thin mucus. Her past medical history included type II diabetes mellitus and hyperthyroidism, which was being treated with insulin, methimazole, and propranolol. The patient initially went to a local hospital on January 22. She received endotracheal intubation and mechanical ventilation due to hypoxemia and was admitted into the intensive care unit (ICU). She had no improvement in the next four days and was then transferred to our hospital. During the admission to our hospital, her temperature, heart rate, respiration rate, and blood pressure (vital signs) were 39.5°C, 188 beats/min, 26 beats/min, and 134/80 mmHg. She was awake but looked lethargic and had labored breathing and coarse bilateral breath sounds without obvious rales or crackles. Laboratory tests measured the white blood cells (11.8×109/L), neutrophils (8.0×109/L), C-reactive protein (72.6 mg/L), procalcitonin (6.1 ng/mL), blood glucose (34.0 mmol/L), hemoglobin A1C (13%), free triiodothyronine (5.8 pmol/L), free thyroxine (25.3 pmol/L), thyroid-stimulating hormone (< 0.005 mIU/L), blood gas analysis (FiO2 50%) pH (6.95), PaCO2 (26 mmHg), PaO2 (184 mmHg), sodium (145 mmol/L), potassium (3.3 mmol/L), base excess (− 26 mmol/L), HCO3 (− 5.8 mmol/L), and lactate (0.6 mmol/L). A urinalysis showed urine ketone 3+, occult blood 3+, protein 2+, and glucose 3+. A computerized chest tomography (CT) scan showed multiple patchy high-density shadows in the bilateral lungs, predominantly in the upper lobes with subpleural distributions (Fig. 1A–C). At admission, she was diagnosed with pneumonia, diabetic ketoacidosis, and hyperthyroidism. She received ceftizoxime and moxifloxacin as the anti-infective treatment, as well as hydration, antihyperglycemic, anti-thyroid, and electrolyte correction managements.
The sputum from the patient was sent for bacterial culture, which reported Burkholderia cepacian and Candida glabrata. The blood culture had no bacterial growth. The 1,3-β-D-glucan was < 10 pg/mL. The bronchoalveolar lavage fluid was sent for mNGS, which reported A. vaginae (10,548 reads, genome coverage rate 26.63%) and G. vaginalis (5,237 reads, genome coverage rate 34.76%) infection (Fig. 2). The mNGS of the blood sample was negative.
The patient was interviewed again. She reported a recent history of increased vaginal discharge with odor for more than one year without treatment. She was in a monogamous relationship and frequently washed her underwear together with other clothing. There was no intrauterine device (IUD) placement. Both A. vaginae and G. vaginalis are commensal vaginal bacteria. The pelvic examination was planned but canceled since she was on her menses. The anti-infective treatment was switched to ceftriaxone 4 g daily combined with ornidazole 0.5 g every 12 h. Her clinical symptoms improved, and the temperature decreased to about 38°C. On January 29, laboratory tests showed white blood cell counts, neutrophil counts, and procalcitonin levels of 6.9×109/L, 5.5×109/L, and 1.4 ng/mL, respectively. CT scan showed multiple patchy shadows in the bilateral lungs, predominantly in the upper lobes, and bilateral pleural effusions with poorly expanded lungs. There were also increased fluid accumulations in the abdominal and pelvic cavities (Fig. 1D–F). A paracentesis was performed with 2,000 ml of yellow transudate drained. The ascitic fluid culture was negative. On January 30, she was extubated after her condition was stable and she was fully awake and alert. The pelvic examination was done, and the vaginal secretion was obtained three days after her menses was completed. The culture revealed the presence of Escherichia coli and Enterococcus faecalis. After treatments, her temperature returned to normal, with no more productive cough. On February 7, laboratory test showed white blood cell and neutrophil counts of 7.7×109/L and 6.2×109/L, and procalcitonin levels of 0.07 ng/mL. CT scan showed a few linear and patchy shadows in the bilateral lower lungs. Compared with the previous CT scans, most of the patchy shadows in both lungs disappeared, with only a small amount of pleural effusion on both sides (Fig. 1G–I). The abdominal and pelvic fluids also disappeared. The dynamic changes of the laboratory test results are presented in Table 1.
Table 1
The laboratory data of this case are presented in the form of timeline.
| | Day 1 | Day 3 | Day 5 | Day 8 | Day 14 |
| Infection | | | | | |
| White blood cell count, ×10^9/L | 11.78 | 10.19 | 6.55 | 6.59 | 6.22 |
| Neutrophil count, ×10^9/L | 7.95 | 8.15 | 5.4 | 4.9 | 4.36 |
| Neutrophil percentage, % | 67.5 | 80 | 82.4 | 74.4 | 70.1 |
| Procalcitonin, ng/ml | 6.08 | 3.55 | 0.563 | 0.073 | 0.058 |
| Organ function | | | | | |
| Alanine aminotransferase, U/L | 83.6 | 52 | 29 | 27.3 | 11.4 |
| Aspartate aminotransferase, U/L | 88.3 | 34.6 | 17.6 | 37.4 | 9.7 |
| Urea nitrogen, mmol/L | 8.12 | 14.58 | 17.17 | 6.96 | 4.14 |
| Serum creatinine, µmol/L | 95.3 | 184.6 | 121.2 | 35.6 | 23.5 |
| Troponin T, ng/L | 56.5 | 47.36 | 30.31 | 29.28 | 17.72 |
| Brain natriuretic peptide, pg/ml | 6286 | 1742 | 1988 | 2997 | 160 |
| Thyroid function | | | | | |
| Free triiodothyronine, pmol/L | 5.82 | | 2.54 | | 6.51 |
| Free thyroxine, pmol/L | 25.26 | | 14.83 | | 27.19 |
| Thyrotropic hormone, mIU/L | < 0.005 | | 0.007 | | 0.005 |