A 73-year-old woman was urgently admitted to the Department of Internal Medicine and Clinical Pharmacology due to shortness of breath, fever, cough, and exercise intolerance. The patient denied direct contact with SARS-CoV-2-infected person in the last 14 days. However, she was not vaccinated against COVID-19. Medical interview showed symptoms of hypertension, diabetes type 2, hyperuricemia, chronic kidney failure in stage G3a according to Kidney Disease Improving Global Outcomes (KDIGO) and paroxysmal atrial fibrillation. Due to the coexistence of comorbidities, the patient had been ordered the following: ramipril, amlodipine, acetylsalicylic acid, chlorthalidone, glimepiride, spironolactone, metformin, allopurinol, and bisoprolol.
In the physical examination on admission, temperature of 36.1 C, blood pressure of 110/60 mmHg, respiratory rate of 24/min, and blood oxygen saturation of 81% were observed, and during lung auscultation, bilateral crackles, wheezing, and decreased respiratory sound in the base parts of lungs were examined. In the electrocardiography, atrial fibrillation with a ventricular rate of 100-130/min was observed. The examination revealed dyspnoea, tachypnoea, and increased work of additional respiratory muscles.
Laboratory tests showed white cells count 16.89 x 103 cells/microL (reference range, 4-10 x 103 cells/microL) with neutrophilia (92.4%) and lymphopenia (5.6%), hemoglobin count 8.5 g/dL (reference range, 11.5-15 g/dL), hematocrit 27.9% (reference range, 36-46%), platelets count 332 x 103 cells/microL (130-400 x 103 cells/microL), C-reactive protein concentration 34.6 mg/L (reference range: 0-5 mg/L), procalcitonin concentration 1.02 ng/mL (reference range: <0.5 ng/mL), interleukin-6 concentration 24.3 pg/mL (reference range: <7 pg/mL), serum creatinine concentration 1.06 mg/dL (reference range: 0.51-0.95 mg/dL), GFR MDRD: 54.01 mL/min (reference range: >60 mL/min), D-dimer concentration 1,040 ng/dL (reference range: <500 ng/dL). ABG showed pH 7.31 (reference range: 7.35-7.45), pCO2 44.3 mmHg (reference range: 35-46 mmHg), pO2 53.3 mmHg (reference range: 70-100 mmHg), SpO2 83% (reference range: >96%), lactate 3.15 mmol/L (reference range: <1.8 mmol/L), base excess (BE) 4.2 mmol/L (reference range: (-2) to 3 mmol/L), and  21.9 mmol/L (reference range, 21-26 mmol/L). Electrolytes, liver enzyme concentration, coagulation, and clinical urine tests were normal.
Due to reported symptoms and laboratory results, COVID-19 was suspected. In order to assess the severity of pneumonia, it was decided to perform lung HRCT. In HRCT bilateral, superimposed air space consolidations with GGO in lowers and uppers lobes, more marked on right were described. Moreover, thickening of the interlobular septa was observed. There were mediastinal hilar lymphadenopathy and bilateral pleural effusion. The lesions accounted for 48% of the lungs. These HRCT findings were described as typical for COVID-19 pneumonia with a moderately advanced British Society of Thoracic Imaging (BSTI) score (Figure 1).
A nasopharyngeal swab sample for SARS-COV-2 was collected three times: two times for antigens tests and one for RT-PCR test. Both antigen tests and RT-PCR tests were negative. Microbiological and mycological blood cultures and sputum cultures were performed. Additionally, there were taken blood tests for the presence of IgM and IgG antibodies for Mycoplasma pneumoniae, Chlamydophila pneumoniae, SARS-CoV-2, Influenza A, B, and Respiratory Syncytial Virus, but they were all negative. Also, abdominal ultrasound examination and echocardiography were performed. No other outbreaks of potential infection were detected.
Before the results of the laboratory tests were obtained, due to the severe clinical condition, empirical therapy was introduced using ceftriaxone, levofloxacin, low molecular weight heparin, dexamethasone, budesonide, and ipratropium bromide.
Due to increasing respiratory failure despite oxygen therapy given and deteriorating results of ABG (pO2: 45.4 mmHg, SpO2: 79%) anesthesiologist's consultation was performed. Prone position and switch type of oxygen therapy to high flow oxygen delivery 60 L/min FiO2: 0.9 was recommended. Moreover, it was recommended to take a nasopharyngeal swab in the SARS-CoV-2 infection one more time, and until the result is obtained, the patient should be treated like a COVID-19-positive person. Recommended procedures improved saturation of patient to 98%; however, this next swab was also negative.
Despite the suggestions of anesthesiologists, remdesivir and tocilizumab were not included in the treatment, suspecting other than viral etiology of pneumonia.
In the cultures following results were obtained: blood and urine were negative, whereas in sputum Candida albicans and Candida glabrata were identified. They were sensitive to fluconazole, amphotericin B, caspofungin, and micafungin. The antifungal drug Fluconazole 200 mg daily per os was added to therapy.
During further hospitalization, improvement in the general state of the patient was observed. Oxygen therapy was gradually reduced. Atrial fibrillation was converted to regular sinus rhythm with ventricular action of 65 beats per minute. On the 10th day, the shortness of breath was not observed, and the patient did not require oxygen therapy (SpO2, 94%). Auscultation of the lung revealed a reduction of crackles and wheezing; the symmetrical respiratory sound was the dominant one. Laboratory determinants of inflammation were normalized. The control chest HRCT showed full withdrawal of inflammatory changes and regression of pleural effusion (Figure 2). At the base of the lungs, fibrous-atelectasis changes were reported.
The patient has been discharged from the hospital in a good general condition without any complaints and continued outpatient treatment with fluconazole.
HRCT scans on hospital admission: bilateral, superimposed air space consolidations with GGO in lower and upper lobes, more marked on right are described.