Autopsy case report
Article Outline
Summary
A 26-year-old woman was admitted to the hospital after experiencing fever, cough and shortness of breath for one week. Despite active rescue remedies, the patient died. To make a definite diagnosis, an autopsy was performed. The patients experiencing such symptoms and processes are typically diagnosed with professional assistance, but the majority of them lack pathological evidence. The diagnosis mainly relies on case history and lung biopsy. Pathologic diagnosis can be achieved through procedures such as a bronchofibroscopic lung biopsy, a thoracoscopic lung biopsy, or an open lung biopsy.
Chief complaint (CC): A 26-year-old woman was admitted to the hospital after experiencing fever, cough and shortness of breath for one week.
History of the present illness (HPI): The patient had been well until one week before admission when the fever began. She did not have chills, but she did begin having a nonproductive cough and shortness of breath, worsened after activity. The temperature fluctuated between 38
°C and 39°C. Shortness of breath occurred by lying down and worsened by any sort of movement, after admission. A chest radiograph showed bilateral, diffuse and reticulonodular opacities. A thoracic Computed Tomography (CT) scan disclosed diffuse, patchy exudation and reticular high-density opacities with obscure boundaries and an unobstructed lobe bronchus. The shortness of breath worsened gradually and presented progressive hypoxic respiratory failure, despite undergoing a series of therapies. These therapies included anti-infection, oxygen inhalation, spasmolysis and enhanced nutritional support. The clinical diagnosis of AIP (Acute Interstitial Pneumonitis) was made primarily on the basis of short course and rapid, violent progression of the disease. Although she underwent large dose prednisolone and mechanical ventilation treatments followed after the diagnosis, dyspnea became more serious with progressive hyoxemia, which was indicated by blood gas analysis (Table 1). Respiratory and cardiac arrests occurred on the 20th day after admission. Despite immediate rescue remedies, the patient died.
Table 1.
| Blood gas analysis | pH | PaCO2 (mmHg) | PaO2 (mmHg) | BE (mmol/L) | HCO3 (mmol/L) | SaO2 (%) | A-aDO2 (mmHg) |
|---|---|---|---|---|---|---|---|
| Admission | 7.456 | 26.6 | 77.5 | −3.0 | 18.2 | 95.9 | 39.3 |
| 10 days after admission | 7.493 | 33.6 | 38.7 | 3.0 | 25.0 | 79.0 | 79.7 |
| 20 days after admission | 7.156 | 29.7 | 29.6 | −15.8 | 10.1 | 35.4 | 86.5 |
Physical examination (PE). Neck: There was no cervical, supraclavicular lymphadenopathy noted. The thyroid was normal. Pulmonary: Lung expansion is symmetric bilaterally. No wheezes or rhonchi noted. Cor or CV (cardiovascular): The heart beat was tachycardic. There were no m/c/r (murmur, clicks, or rubs). Abd (abdomen): The abdomen revealed normal active bowel sounds. There was no rebound or guarding. The liver and spleen were not palpable. Extremities: There was no evidence of clubbing or cyanosis. There was no femoral, axillary, or epitrochlear lymphadenopathy noted.
As indicated above, prednisolone stosstherapy and mechanical ventilation had no significant therapeutic effect for the disease. Abrupt onset and dangerous pathogenetic conditions were the primary characteristics in this case. Aside from those symptoms similar to an upper respiratory virus infection in the first days of the patient's illness, no fundamental disease or other etiological factors existed. Therefore the AIP was made first. To make a definite diagnosis, an autopsy was performed. The autopsy indicated both lungs weighed 1400g. The left and right lung volumes were 22×13×5cm and 22×13×7cm, respectively. Both lung surfaces were smooth and glossy, and a small amount of fibrinous adhesion was found among the pulmonary lobes. Its cross-section showed kermesinus with some red liquid matter leaking out. Its texture was hard. Microscopical examination showed diffuse, marked alveolar septal edema with fibroblast proliferation, collagen fibrillation, lymphocyte infiltration, and occasional hyaline membranes (Figure 1, Figure 2, Figure 3). The septa were lined with hyperplastic cubic alveolar epithelial cells, more exudation and phagocytes in alveolar space, bronchial epithelium autolysis with occasional squamous metaplasia, significant arterial vein ectasia and congestion, and hyperplastic pulmonary endarterium. Tongue-shaped hyperplastic type II pneumocytes filled some air spaces and collapsed, and organized thrombi developed in the small arteries. In addition to her clinical history, the result of the autopsy was consistent with pathological changes of AIP. In conclusion, the patient died of progressive respiratory failure caused by pulmonary interstitial fibrosis.
Figure 1
Figure 2
Figure 3
In 1944, Hamman and Rich described a group of patients with rapidly progressive respiratory illness of unknown etiology. All patients experienced insidious onset followed by a cough, respiratory embarrassment and respiratory failure, and progressive pulmonary interstitial fibrosis in both lungs. They all died within 2–6 months of initial onset. In addition, sections from their post-mortem lungs indicated pulmonary edema with areas of hyaline membrane formation and diffuse, and hyperplastic septal fibrous tissue. With these conditions, term “acute diffuse interstitial fibrosis of the lung” was introduced. In subsequent publications, the eponym Hamman–Rich Syndrome has been used to describe the cases of diffuse pulmonary fibrosis. In 1986, Katzenstein reported eight similar cases to the Hamman–Rich Syndrome. They all had acute respiratory failure and were treated with mechanical ventilation within 1–2 weeks after onset.1 Histological examination revealed marked alveolar septal edema with inflammatory cell, infiltration, active fibroblast proliferation, extensive alveolus damages, and hyaline membranes formation. Among them, seven patients died after half a year, and only one patient recovered. Katzenstein replaced Hamman–Rich Syndrome with the term “Acute Interstitial Pneumonitis” to more specifically describe the idiopathic interstitial lung disease.
AIP is a rare interstitial form of pneumonia characterized by rapid progression process and peculiar histological features, including 2% of pulmonary interstitial fibrosis. It can occur at any age and has no gender predilection. The patients suffering from AIP experience abrupt onset followed by symptoms similar to upper respiratory virus infection. These last several days to several weeks in the initial stage. As AIP develops rapidly, the patients may die anywhere from two weeks to six months depending on the time of diagnosis and treatment.
Fundamental CT scan manifestations of AIP contain diffuse bilateral consolidation, reticular opacity, tiny nodules, and ground-glass opacity. They are accompanied by traction bronchiectasis, architectural distortion, thickening of the interlobular septum and honeycombing. HRCT can help confirm the progression and extension of AIP, such as reversible or irreversible pathological changes. For example, if an irreversible pulmonary changes during a terminal stage the patient can forego a biopsy. CT manifestations of AIP should be identified with ARDS, common pneumonia, pulmonary alveolar microlithiasis and bronchial alveolar cell carcinoma.
The lung function test can show decreased function of diffusion and limited ventilation dysfunction.
Irreversible hypoxia occurs in the early stages and rapidly progresses to respiratory failure. Patients most likely will need mechanical ventilation.
The oxygenation index is ≤200mmHg in the majority of AIP patients.
So far, there are no well-defined therapies for AIP which carries a high mortality rate up to 50% or even higher. For AIP survivors, the disease may experience recurrences and chronic progressive interstitial lung disease.2, 3
The patients experiencing such symptoms and processes are typically diagnosed with professional assistance, but the majority of them lack pathological evidence. The diagnosis mainly relies on case history and lung biopsy. Pathologic diagnosis can be achieved through procedures such as a bronchofibroscopic lung biopsy, a thoracoscopic lung biopsy, or an open lung biopsy. Antibiotic therapy is ineffective for AIP which may be relieved or cured via the administration of full-dose glucocorticoid during early stages of the disease.
Conflict of interest statement
The authors have no conflicts of interest to declare.
References
PII: S1755-0017(08)00054-7
doi:10.1016/j.rmedc.2008.07.009
© 2008 Elsevier Ltd. All rights reserved.
