A 39-year-old female Caucasian psychologist sought medical attention complaining of cough. Chest radiography showed changes that were attributed to pneumonia, treated with cefuroxime at the time. After eight months, progressive dyspnea was associated.
Initial diagnosis by pulmonologist was "organizing pneumonia," based on clinical history and computed tomographic (CT) findings, described as "focal areas of lung parenchymal infiltrates with ground-glass opacities, associated with septal thickening, with peripheral distribution, predominating in the lower lobes" (Figures 1(a) and 1(b)). Transbronchial biopsy was performed, which showed "scant fragments of bronchial wall and adjacent alveolar collapse exhibiting a minimum focus of interstitial inflammatory infiltrate." It was prescribed treatment with prednisone 20 mg/day.
After twelve months of evolution since the onset of symptoms, she went to a rheumatologist for differential diagnosis evaluation. On this occasion, the pulmonologist had already searched and excluded tuberculosis and she had dyspnea on minimal exertion. Diffuse pain in arms and legs, burning in the fingertips, fatigue, sleep disorder, Raynaud's phenomenon (RP), xerostomia, and xerophthalmia were present at the symptomatology interrogation and physical examination. She had positive personal and family history of Hashimoto's thyroiditis. On physical examination there was no skin thickening or arthritis, oroscopy was normal, blood pressure was 90 x 60 mmHg, and heart frequency was 96 beats per minute. Upon respiratory system examination basal crackles bilaterally and 20 breaths per minute were observed. There were no changes in cardiovascular and abdominal examination.
Tests were requested for the investigation of rheumatic diseases including systemic sclerosis, Sjogren's syndrome, and vasculitis. On this occasion, the prednisone dose was increased to 1 mg/kg/day.
Inflammatory activity tests and serologic and antibodies tests are demonstrated in Table 2.
In the evaluation of lung function a pattern compatible with incipient restrictive ventilatory disorder was observed. As evidence of inflammatory activity, CRP was always negative and ESR was increased. Autoantibodies were negative (antinuclear antibodies-ANA, rheumatoid factor, anti-SCL 70, anti-Jo-1, anti-RNP, anti-SS-A, anti-SS-B, and c-ANCA), except a 1 : 20 p-ANCA reagent. The patient presented a normocytic normochromic anemia, and the hemoglobin value ranged from 9.8 to 13.3 mg/dL and the hematocrit range was 30.3 to 41.7%, probably due to the underlying disease. In two occasions, the patient presented lymphopenia that could indicate disease activity or could be related to steroid therapy. Chlamydia pneumonia IgG serology was reagent 1 : 512 and IgM was negative. Mycoplasma pneumonia serology was negative. The exams allowed excluding Sjogren's syndrome (negative anti-SS-A and anti-SS-B and normal salivary biopsy). Renal, liver, and hormonal functions were normal.
A panoramic nailfold capillaroscopy showed the presence of moderate capillary ectasia and mild devascularization of focal distribution, described as "well-defined scleroderma (SD) standard microangiopathy, consistent with systemic sclerosis, dermatomyositis or overlap syndrome with scleroderma component" (Figure 2). 
Given the results of capillaroscopy and the presence of RP she was diagnosed with systemic sclerosis in the early stages. Then it was proposed to start cyclophosphamide pulse 1 g.
However, after three weeks of diagnosis, the patient developed high fever (39 degrees) and dyspnea at rest, requiring hospitalization. On admission, her respiratory frequency was 40 incursions per minute, the arterial oxygen tension was 48.4 mmHg, and oxygen saturation was 88.5% and she had basal crackles bilaterally. On the third day she developed respiratory failure, requiring ventilatory support and intensive care. The chest CT showed interstitial infiltrate, with diffuse ground-glass opacity in both lungs, associated with foci of parenchymal densification, predominantly peripheral, some air bronchograms and mild pleural thickening marginally, more evident in right lung basis and apex. Small calcified nodules of residual aspect, scattered in both lungs, without pleural effusion (Figures 1(c) and 1(d)), were observed. An echocardiogram was done to exclude pulmonary hypertension. The pulmonary arterial pressure was 31 mmHg.
Hemoculture and urine culture were negative. Virus B and C serologies were negative. The CRP increased from 42 to 147 mg/dL.
At that moment the pulmonologist considered three possible diagnosis: nonspecific interstitial pneumonia, pneumonia caused by Pneumocystis carinii, or pneumonia caused by virus (CMV, adenovirus, herpes 1 and 2).
On the fourth day, she underwent an open biopsy (microthoracotomy), which consisted of pulmonary segmentectomy of right middle and lower lobes. Some part of the material was sent to investigate fungus, mycobacteria, and general culture, all of them presented negative results. The biopsy revealed that there were no infectious process and no granulomas. Histopathological examination showed "a parenchymal diffuse involvement, intra-alveolar fibrin accumulation in the form of solid blocks, pneumocytes hyperplasia, interstitial mild acute inflammatory infiltrate, alveolar septal edema and congestion, intra-alveolar fibroblastic Masson bodies and xantomatososum  accumulation of macrophages, a typical pattern of acute Fibrinous and Organizing Pneumonia (AFOP)" (Figure 1(e)).
After excluding any infection etiology including bacteria, virus, mycobacteria, and fungus, she received pulse therapy with cyclophosphamide 1 g and methylprednisolone 1 g for three days. Despite treatment, the patient developed respiratory failure by pulmonary hemorrhage.