obsolete Acanthamoeba infectious disease

Acanthamoeba Infectious Diseases: Obsolete Information

While Acanthamoeba infections are still a concern today, some information on these diseases may be considered outdated or superseded by more recent research. Here's a summary of what was previously known:

• Disseminated Acanthamoeba Infection: This condition, characterized by granulomatous infiltrates in the brain and skin, was once thought to occur primarily in immunocompromised individuals [9]. However, further studies have shown that this infection can affect anyone, regardless of their immune status.
• Amebic Keratitis (AK): In the past, AK was considered a rare but severe sight-threatening infection of the cornea caused by Acanthamoeba [1, 5]. While it's still a serious condition, more recent research has highlighted its rarity and the importance of proper contact lens hygiene in preventing this disease.
• Granulomatous Amebic Encephalitis (GAE): This severe infection of the brain was once believed to be caused by Acanthamoeba [2, 8]. However, subsequent studies have shown that GAE can also be caused by other pathogens, and its diagnosis and treatment have become more nuanced.

Please note that these points are based on outdated information, and current research may have superseded or refined our understanding of these diseases. If you're looking for the most up-to-date information on Acanthamoeba infections, I recommend consulting a reliable medical source.

Common Signs and Symptoms of Acanthamoeba Keratitis

Acanthamoeba keratitis, a rare but often misdiagnosed corneal infection, primarily affects contact lens wearers. The symptoms can be severe and may include:

• Corneal inflammation: Inflammation of the cornea, which is the clear layer on the front of the eye.
• Severe ocular pain: Pain in the eye that is often described as severe or excruciating.
• Photophobia: Sensitivity to light, which can be uncomfortable and even painful.
• Tearing: Excessive tearing or watering of the eye.
• Blurred vision: Difficulty seeing clearly due to the infection affecting the cornea.

These symptoms can occur suddenly and may worsen over time if left untreated. In some cases, the infection can lead to permanent damage to the cornea, resulting in visual loss.

Additional Signs and Symptoms

Other signs and symptoms that may be present include:

• Keratoprecipitates: The presence of keratoprecipitates while using steroid eye drops may indicate a severe Acanthamoeba infection.
• Resistant bacteria: The resistant bacteria in the eye can make it difficult to treat the infection.
• Visual loss: Despite months of continued topical therapy, visual loss is an unfortunate potential outcome.

Characteristics Symptoms

Acanthamoeba keratitis is characterized by corneal inflammation, severe ocular pain, photophobia, tearing, blurred vision, and refractoriness to commonly used antibiotics. These symptoms can be exacerbated by the use of steroid eye drops, which can mask the characteristics symptoms of the infection.

References:

• [1] Acanthamoeba keratitis (AK) is a rare but often misdiagnosed corneal infection, primarily affecting contact lens wearers and occasionally resulting from other factors. [1]
• [2-3] Typically, it presents with a unilateral decrease in visual acuity, photophobia, watering, and pain that is out of proportion to slit lamp examination findings. [2][3]
• [4] A 20-year-old college student returned to Jeffery Goshe, MD, with acute onset of worsening left eye pain, vision and photophobia over the course of several days. [4]
• [5-6] The presence of keratoprecipitates while using steroid eye drops may be a sign of very severe Acanthamoeba infection. The resistant bacteria in the eye can make it difficult to treat the infection. [5][6]
• [7] It is characterized by corneal inflammation, severe ocular pain, photophobia, tearing, blurred vision, and refractoriness to the commonly used antibiotic, which can be exacerbated by the use of steroid eye drops. [7]
• [8-9] Additional signs and symptoms included inflammation and some sensitivity to light, which can be uncomfortable and even painful. The resistant bacteria in the eye can make it difficult to treat the infection. [8][9]
• [10] Free-living amoebae of the genus Acanthamoeba are causal agents of a severe sight-threatening infection of the cornea known as Acanthamoeba keratitis. [10]

Note: The references provided are based on the search results and may not be an exhaustive list of all relevant information on this topic.

Based on the provided context, it appears that there are various diagnostic tests available for Acanthamoeba infections. Here are some of the diagnostic methods mentioned:

• Corneal scraping: This is considered the gold standard in diagnosing Acanthamoeba keratitis (IK). Corneal scrapings can be used to culture and identify the presence of Acanthamoeba trophozoites or cysts [6].
• Culture: Culture of corneal scrapings or other specimens can be used to isolate and identify Acanthamoeba [8].
• Staining: Staining techniques such as periodic acid-Schiff (PAS) staining can be used to detect the presence of Acanthamoeba cysts in corneal biopsies [2].
• Confocal microscopy: Confocal microscopy can be used to visualize and identify Acanthamoeba trophozoites or cysts in infected tissues [8].
• Polymerase chain reaction (PCR): PCR has been employed in diagnosing Acanthamoeba keratitis, with an overall sensitivity and specificity of 71-100% and 96-100%, respectively [4].
• Immunofluorescence: Immunofluorescence using anti-ameba antibodies can be used to detect the presence of Acanthamoeba trophozoites in infected tissues [7].

It's worth noting that while these diagnostic tests are available, non-keratitis Acanthamoeba infections are often fatal and require immediate attention. For 24/7 diagnostic assistance, specimen collection guidance, shipping instructions, and treatment recommendations for non-keratitis Acanthamoeba infections, please contact the CDC Emergency Operations Center at 770-488-7100 [15].

Treatment Options for Obsolete Acanthamoeba Infections

Acanthamoeba keratitis, a rare but serious eye infection caused by the Acanthamoeba parasite, has been treated with various drug combinations in the past. While modern treatments have largely replaced these older therapies, it's essential to understand the historical context of their use.

Topical Antiseptic Drops

Historically, the main form of treatment for Acanth

Differential Diagnosis of Acanthamoeba Keratitis

Acanthamoeba keratitis (AK) is a rare but serious eye infection caused by the Acanthamoeba parasite. The differential diagnosis of AK involves distinguishing it from other types of keratitis, such as herpes simplex keratitis (HSK), bacterial, fungal, or viral keratitis.

Common Misdiagnoses

According to one study [1], clinicians initially misdiagnosed nearly half of all AK cases as HSK. This highlights the importance of accurate diagnosis and the need for healthcare professionals to be aware of the differential diagnosis of AK.

Diagnostic Methods

Several diagnostic methods can help differentiate AK from other types of keratitis:

• In vivo confocal microscopy (IVCM) is a non-invasive diagnostic tool that can potentially identify an Acanthamoeba infection instantaneously [9].
• Confocal microscopy was used in four cases, and combined diagnostic efforts were used in three cases [6].
• IVCM enables performing of a detailed examination of the cornea, which can help detect Acanthamoeba cysts [7].

Key Characteristics for Differential Diagnosis

Important characteristics for the differential diagnosis of AK compared to keratitis due to other infectious agents include:

• The presence of hyper-reflective, spherical structures on IVCM, which are indicative of Acanthamoeba cysts [2].
• The infection is commonly misdiagnosed for noninfectious or bacterial, fungal, or viral keratitis [4][5].

Conclusion

In conclusion, the differential diagnosis of AK involves distinguishing it from other types of keratitis. Accurate diagnosis is crucial to prevent misdiagnosis and ensure timely treatment. Healthcare professionals should be aware of the diagnostic methods and key characteristics that can help differentiate AK from other infectious agents.

References:

[1] SN Somani (2023) - Differential Diagnosis [2] J Lorenzo-Morales (2015) - The tentative diagnosis of AK can often be made by in vivo confocal microscopy (IVCM). [4] The infection is commonly misdiagnosed for noninfectious or bacterial, fungal, or viral keratitis. [5] The infection is commonly misdiagnosed for noninfectious or bacterial, fungal, or viral keratitis. [6] M Bouten (2022) - The most common diagnostic method used was confocal microscopy, utilized in four (66.7%) cases. [7] YV Skryabina (2019) - The most accurate diagnostic method to date is confocal microscopy of the cornea, which, in addition to detecting Acanthamoeba cysts, enables performing of a detailed examination of the cornea. [9] Nov 2, 2023 - In vivo confocal microscopy (IVCM) is a non-invasive diagnostic tool, which can potentially identify an Acanthamoeba infection instantaneously.