Histologic Findings

In keratitis, amebic cysts and trophozoites are found within the cornea. An acute or mixed inflammatory infiltrate may contain giant cells. Corneal revascularization may occur.

Individuals with GAE have moderate-to-severe cerebral edema. Necrotizing granulomas that contain perivascular trophozoites and cysts are usually located in the cerebellum, mid brain, and brain stem. Multinucleated giant cells may be present within the granulomas. Granulomas are usually noted among immunocompetent patients. On biopsy specimens, angiitis with perivascular cuffing with lymphocytes may be seen. The leptomeninges are spared except when they directly overlie areas of cortical involvement.

Other Tests

Based on animal models, polymerase chain reaction (PCR) testing appears to be a promising method of rapid keratitis diagnosis.^[22]

Treatment & Management

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Author

Theresa M Fiorito, MD, MS, FAAP, CTH® Assistant Professor of Pediatrics and Pediatric Infectious Diseases, NYU Long Island School of Medicine; Attending Physician, Pediatric Infectious Diseases, Director, Family Travel Clinic, NYU Winthrop Hospital; Attending Physician, Pediatric Infectious Diseases, Hassenfeld Children's Hospital at NYU Langone

Theresa M Fiorito, MD, MS, FAAP, CTH® is a member of the following medical societies: American Academy of Pediatrics, Infectious Diseases Society of America, International Society of Travel Medicine, Pediatric Infectious Diseases Society

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Richard B Brown, MD, FACP Chief, Division of Infectious Diseases, Baystate Medical Center; Professor, Department of Internal Medicine, Tufts University School of Medicine

Richard B Brown, MD, FACP is a member of the following medical societies: Alpha Omega Alpha, American College of Chest Physicians, American College of Physicians, American Medical Association, American Society for Microbiology, Infectious Diseases Society of America, Massachusetts Medical Society

Disclosure: Nothing to disclose.

Chief Editor

Pranatharthi Haran Chandrasekar, MBBS, MD Professor, Chief of Infectious Disease, Department of Internal Medicine, Wayne State University School of Medicine

Pranatharthi Haran Chandrasekar, MBBS, MD is a member of the following medical societies: American College of Physicians, American Society for Microbiology, International Immunocompromised Host Society, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Additional Contributors

David R Haburchak, MD, FACP Key Faculty, Wellstar Kennestone Internal Medicine Residency Program, Wellstar Health System

David R Haburchak, MD, FACP is a member of the following medical societies: American College of Physicians, American Osler Society, American Society for Microbiology, Christian Medical and Dental Associations, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

David Hall Shepp, MD Program Director, Fellowship in Infectious Diseases, Department of Medicine, North Shore University Hospital; Associate Professor, New York University School of Medicine

David Hall Shepp, MD is a member of the following medical societies: Infectious Diseases Society of America

Disclosure: Received salary from Gilead Sciences for management position.

Nancy F Crum-Cianflone, MD, MPH Consulting Staff, Department of Internal Medicine, Division of Infectious Diseases, Naval Medical Center at San Diego

Nancy F Crum-Cianflone, MD, MPH is a member of the following medical societies: Alpha Omega Alpha, American College of Physicians, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Acknowledgements

The authors and editors of Medscape Reference gratefully acknowledge the contributions of previous coauthor William B. Harley, MD, to the development and writing of this article.

Acanthamoeba Infection Workup

Histologic Findings

Other Tests

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