Toxic corneal reaction due to exposure to palytoxin

A case is presented of corneal toxicity after exposure to palytoxin. A 42 year-old man came with symptoms of pain and blurred vision in his right eye. He reported that a zoanthid coral from a saltwater aquarium had squirted into his eye. Slit-lamp examination showed a prominent central ring infiltrate of 4×6mm without epithelial defect and satellite sub-epithelial micro-infiltrates. After 2 months of topical treatment with steroids, the stromal ring infiltrate was resolved, but a stromal thinning and residual fibrosis remained. Palytoxin is a potent vasoconstrictor that damages the ionic gradient of the cells, causing cell death. It is crucial to remove the toxin and start an aggressive topical therapy as soon as possible. In addition, considering the potential ocular and systemic adverse effects that this toxin can produce, it would be advisable to inform people of its existence and regulate the distribution of this type of corals.

High level of interferon gamma in tuberculous pleural effusion

It has been observed that T-lymphocytes of patients with tuberculosis produce interferon gamma (IFN gamma) in vitro. Based on this idea, we studied IFN gamma in pleural fluid and serum. We studied 80 patients with pleural effusion; 30 patients with tuberculous pleurisy had high IFN gamma concentrations in pleural fluid. Patients with malignant pleural effusions, nonspecific pleural effusion, parapneumonic effusions and pleural transudates had low levels. The IFN gamma levels were higher in those with massive tuberculous effusion and apparent pulmonary lesion on x-ray film. We found that the T4/T8 lymphocyte ratio was higher in pleural fluid than in peripheral blood. Numbers of T3 and T4 lymphocytes were higher in tuberculous pleural effusions compared with those in other patients. There is no correlation between IFN gamma levels and lymphocyte subsets in pleural effusion. Perhaps pleural T-lymphocytes produce IFN gamma after stimulation by mycobacterial antigens and this lymphokine activates macrophages, increasing their bactericidal activity against Mycobacterium tuberculosis.