Acute Flaccid Paralysis Accompanying West Nile Meningitis Ahmed ...

Delayed Paclitaxel-Induced Interstitial Pneumonitis With Impressive Resolution
Palmer, C, D.O. Merolli, A, M.D.
Kent Hospital, Internal Medicine Residency Program, Warwick RI.
Introduction: Drug Induced Lung Disease (DILD) often due to medications, herbals, or
illicit drugs. Common offenders include NSAIDS, ACE Inhibitors, Methotrexate, and
Amiodarone. Patterns of DILD include diffuse alveolar hemorrhage, hypersensitivity
pneumonitis, interstitial lung disease, etc. The chemotherapy agent, Paclitaxel, is a rare
cause of DILD. It's a serious condition that can lead to acute respiratory failure requiring
mechanical ventilation. We have a case of a 48 year old female with history of recurrent
stage IIIA ovarian cancer receiving paclitaxel chemotherapy presenting with hypoxia.
Case: A 48-year-old female with a history of recurrent stage IIIA ovarian cancer was
admitted to the hospital with worsening abdominal pain and plan for laparotomy. She
had completed her last of three cycles of Paclitaxel over three weeks prior to
presentation. Unfortunately, on exploratory laparotomy she was found to have extensive
abdominal metastatic disease, so the plan was medical management only.
Postoperatively she was hospitalized for decreased urine output and abdominal pain
requiring a patient-controlled analgesic pump. On postoperative day three, her oxygen
saturation was found to be low at rest and 70% with ambulation. At this time she
admitted to a two to three week history of dyspnea on exertion, but denied any sensation
of acute shortness of breath. At that time she was febrile at 38.4C and tachycardic at
112bpm. Her exam was significant for bilateral lower extremity edema and right sided
expiratory wheezing. A chest radiograph was performed revealing bilateral diffuse
infiltrates without effusions. Her labs revealed a normal leukocyte count, normal B-
Natriuretic Peptide, and negative blood cultures. The surgical team diuresed the patient
based on radiology report. Twenty four hours later, she had a second hypoxic episode
while on oxygen. At this time, pulmonary embolism was ruled out with a chest CT scan,
but results revealed impressive symmetric bilateral ground glass opacities sparing the
peripheral lung fields. The radiology report communicated concern for pulmonary
edema versus bilateral pneumonia. At this point medical consultation was obtained.
Although there is a broad differential for ground glass opacifications, the diagnosis was
most consistent with interstitial/hypersensitivity pneumonitis with evidence of alveolar
filling defects. Intravenous steroids were initiated and within 48-72 hours the patient's
clinical picture markedly improved. Due to the patient reported chronicity and the CT
findings we had come to the conclusion that this was unlikely infectious and more likely a
Paclitaxel-induced hypersensitivity interstitial pneumonitis. Repeat chest CT one month
later revealed complete resolution of the pneumonitis.
Discussion: DILD secondary to Paclitaxel dosed every three weeks as in this case
occurs in less than 1% of patients. Case reports have indicated the importance of
recognizing and treating this condition early. Although most cases have documented
pulmonary toxicity within minutes to hours after Paclitaxel infusion, the rarer delayed
hypersensitivity effects can manifest weeks following treatment. Keeping this in mind,
physicians must recognize that DILD can occur long after Paclitaxel administration and
intravenous steroids need to be administered immediately. This case also emphasizes
the importance of reading one’s own radiological images and generating a differential
diagnosis regardless of the official report.