Infantile digital fibromatosis (IDF), also termed inclusion body fibromatosis, Reye tumor, or Reyes tumor, usually occurs as a single, small, asymptomatic, nodule in the dermis on a finger or toe of infants and young children. IMF is a rare disorder with approximately 200 cases reported in the medical literature as of 2021. The World Health Organization, 2020, classified these nodules as a specific benign tumor type in the category of fibroblastic and myofibroblastic tumors. IDF was first described by the Australian pathologist, Douglas Reye, in 1965.IDF consists of an overgrowth of spindle-shaped cells in a collagen fiber-rich background located in the dermis (i.e. the layer of skin between the  epidermis and subcutaneous tissue) but may extend into the subcutaneous tissue. These spindle-shaped cells contain distinctive inclusion bodies within their cytoplasm that greatly help in distinguishing IDF from other fibrous skin diseases. These inclusions are composed of densely packed vimentin and actin filamentsIDF lesions are usually painless and  have a tendency to regress spontaneously. Consequently, the current recommended treatment for IDF nodules is conservative observation. If the lesions cause local deformities and/or functional impairments or continue to increase in size over long observation periods, surgical removal is recommended. However, surgically removed IDF lesions have had high rates of recurrence and this surgery may cause post-operative digital deformities.
The use of the sympathomimetic drug causes the iris dilator muscle to be directly stimulated, causing increased dilation. In the United States, the sympathomimetic drop most commonly used along with tropicamide, is 2.5% phenylephrine hydrochloride (brand name AK-Dilate). Side effects
Tropicamide induces transient stinging and a slight and transient rise in intraocular pressure in the majority of patients. It may cause redness or conjunctivitis (inflammation) and also blurs near vision for a short while after instillation (care must be taken, and the patient must only drive when vision returns to normal). Tropicamide may, in very rare cases, cause an attack of acute angle-closure glaucoma. This tends to be in patients with narrow anterior chamber angles, and closure risk must be assessed by the practitioner prior to instillation. Tropicamide is often preferred to atropine because atropine has a longer half-life, causing prolonged dilation and blurry vision for up to a week. Atropine has less sting effect, but can be toxic or fatal if ingested in large quantities by children or adults. With eye drops, systemic effects are minimal to nonexistent due to very low absorption into the bloodstream. Illicit use
According to the researchers of the European Commission-funded ReDNet Project, in Russia tropicamide is currently abused (injected intravenously) as an inexpensive recreational deliriant drug. Stereochemistry
Tropicamide has a chiral center and two enantiomers. Medications are racemates. References
External links
"Tropicamide". Drug Information Portal. U.S. National Library of Medicine.