Pulmonary palytoxin poisoning on CT imaging

ABSTRACT

Background: Palytoxin poisoning is an uncommon exposure in the US, and is most frequently encountered amongst hobbiests and professionals in the aquarium industry. The toxin is produced by the microalgae Ostreopsis as well as the coral Palythoa toxica. Discovered in Hawaii, the name limu-make-o-Hana translates to "seaweed of death from Hana." Palytoxin interrupts Na+/ K+ ATPase pump, resulting in widespread cellular dysfunction. Persons are at highest risk when cleaning a fish tank housing the coral that produces palytoxin, resulting in cutaneous or inhalational exposure. We present a case of palytoxin inhalational exposure with computed tomography (CT) imaging. Case report A 41-year-old male presented to the emergency department (ED) with dyspnea, cough, and wheezing after cleaning his saltwater fish tank. He reported that he maintains Zoanthid corals in his home saltwater fish tank and typically wears personal protective equipment when cleaning the tank. He had taken off his mask directly after using hot water to clean the tank, and quickly developed shortness of breath. He contacted Poison Control and was instructed to take loratadine with initial improvement in his symptoms. He then developed decreased appetite, nausea, and chills. The following day, in addition to these symptoms, he developed a fever of 102.5 degreeF and an oxygen saturation of 88% measured with an at-home pulse oximeter. He then proceeded to the ED where he was found to be hypoxic to 91% on room air, tachycardic to 120 bpm, hypotensive to 93/ 70mmHg, febrile to 100.9 degreeF and tachypneic at a respiratory rate of 30. Physical exam revealed clear lung sounds. Application of supplemental oxygen at 2 L resulted in improvement in his oxygen saturation and his hypotension and tachycardia responded to intravenous fluids. Significant laboratory results included WBC count of 20.4 with bands of 14%, elevated lactate of 2.4mmol/L, elevated D-dimer of 0.48 mug/mL and a negative COVID PCR test. CTA thorax revealed patchy ground-glass opacities in the bilateral upper and lower lobes with mosaicism. The patient received doxycycline in addition to broad spectrum antibiotics due to concern for inhalational marine toxicity. He was also started on 60mg prednisone, inhaled steroids, and bronchodilators for symptomatic treatment, with improvement in his symptoms. During his hospitalization, a respiratory viral panel was negative for common viruses associated with atypical pneumonia including influenza, coronavirus, metapneumovirus, rhinovirus, enterovirus, adenovirus, parainfluenza, bocavirus, Chlamydophila pneumoniae, and Mycoplasma pneumonia. His dyspnea gradually improved and he was weaned off supplemental oxygen prior to discharge home on hospital day 2. Discussion(s) It is unclear what changes are expected on thoracic imaging in patients with inhalational palytoxin exposure. Chest radiographs in two previous cases displayed scattered infiltrates, and a chest CT in another case showed pleural based consolidations. The ground-glass mosaicism suggests that a more diffuse reactive airway process after an inhalational palytoxin insult. Conclusion(s) Patients with inhalational palytoxin exposure may be found to have reactive airway symptoms along with ground glass opacities with mosaicism on CT imaging.