Correct!
5. Surgical lung biopsy
Given the pulmonary parenchymal findings, a surgical lung biopsy may be the single best procedure to obtain a unifying diagnosis for this patient. Brain biopsy is quite invasive, and, as noted previously, may not yield the desired information, particularly given that treatment, which could alter biopsy results, has been instituted for some time. Additionally, the likelihood of central nervous system vasculitis is now low, in light of the lumbar puncture and cerebral angiogram results; rather, an extracranial embolic source for the brain parenchymal changes seems more likely. Bronchoscopy with bronchoalveolar lavage and transbronchial biopsy is a reasonable thought, but has been performed recently without a definitive diagnosis, and therefore the yield of repeating this procedure is low, and the review of the material performed at the bronchoscopy at the outside facility just prior to the patient’s admission is still pending. Percutaneous transthoracic needle biopsy of the lung is typically utilized for focal lesions, not for the diffuse abnormalities affecting this patient’s lung parenchyma. Myocardial biopsy may be used in patients with heart transplant to assess for rejection or for patients with myocardial dysfunction thought to the related to myocarditis or non-ischemic cardiomyopathy, but this patient’s left ventricular mechanics are normal, and biopsying the right heart would not provide data that could establish the etiology of her pulmonary hypertension. A surgical lung biopsy, despite associated risks given the pulmonary hypertension, is probably the best procedure for establishing the etiology of the pulmonary hypertension and abnormalities seen at chest CT and perhaps even the brain MRI findings, the latter particularly in light of the patent foramen ovale. Note that cryobiopsy could play a role here as a less invasive means for obtaining lung tissue for diagnosis compared with surgical biopsy, but this choice was not listed above.
The patient was scheduled to undergo video-assisted thoracoscopic lung biopsy, but lung biopsy material obtained from her outside facility bronchoscopy with transbronchial biopsy showed perivascular refractile crystalline material consistent with microcrystalline cellulose, associated with granulomas suggesting a foreign body reaction. This discovery prompted a pointed discussion with the patient, who then admitted to crushing hydrocodone tablets and injecting them intravenously; she had previously denied substance abuse, even when directly asked pointed questions regarding the injection of illicit drugs. The open lung biopsy procedure was deferred, as the patient’s pulmonary hypertension and central nervous system abnormalities are readily explained by intravenous injection of a foreign substance causing pulmonary arteriolar obstruction and pulmonary hypertension, with the patient foramen ovale allowing systemic embolization of the injected material, resulting in embolic cerebral infarction. Psychiatry was consulted to assist in management of the patient’s substance abuse.
Diagnosis: Pulmonary hypertension and cerebral infraction resulting from intravascular embolization of hydrocodone in an injection drug user with a patent foramen ovale
References