A 14-year-old girl with a rare metabolic disorder called hereditary tyrosinemia type 1 developed painful eye problems that looked exactly like a herpes infection. Doctors initially treated her with antiviral medications, but these didn’t help. Advanced imaging tools revealed the real problem: crystal-like deposits in her eyes caused by her metabolic condition. When she returned to a strict low-protein diet and stopped the unnecessary antiviral drugs, her eye symptoms improved significantly. This case shows how important it is to consider rare metabolic diseases when eye infections don’t respond to standard treatments.

The Quick Take

  • What they studied: How a rare metabolic disease called hereditary tyrosinemia type 1 can cause eye problems that look like a herpes infection but actually need different treatment
  • Who participated: One 14-year-old girl with hereditary tyrosinemia type 1 who had been diagnosed with the condition since infancy
  • Key finding: The patient’s eye lesions (sores) that resembled herpes actually improved when she followed a strict low-protein diet and stopped taking antiviral medications, suggesting the problem was metabolic, not infectious
  • What it means for you: If you or someone you know has a rare metabolic disorder and develops eye problems that don’t respond to standard treatments, doctors should consider whether the eye problem is connected to the metabolic condition rather than assuming it’s an infection

The Research Details

This is a case report, which means doctors documented the medical history and treatment of one patient with an unusual presentation. The 14-year-old girl came to a specialized eye center complaining of light sensitivity and eye discomfort in both eyes. Doctors used two advanced imaging techniques to examine her eyes: in vivo confocal microscopy (a special microscope that takes detailed pictures of the eye’s surface layers) and anterior segment optical coherence tomography (a scanning technology similar to ultrasound but using light instead of sound waves). These tools allowed doctors to see crystal-like deposits in her corneas (the clear front part of the eye) that weren’t visible with standard eye exams.

This research approach is important because it shows how advanced imaging tools can help doctors distinguish between similar-looking eye conditions. The case demonstrates that when standard treatments fail, doctors should reconsider their diagnosis. By documenting this patient’s journey from misdiagnosis to correct treatment, the doctors provide valuable information that can help other physicians recognize similar cases in the future.

This is a single case report, which is the lowest level of scientific evidence. However, case reports are valuable for identifying rare disease presentations and unusual treatment responses. The strength of this case is that it includes detailed imaging documentation showing improvement with treatment. The main limitation is that findings from one patient cannot be generalized to all people with this condition. The patient’s incomplete adherence to her diet before treatment makes it harder to determine exactly which factor (diet alone or diet plus stopping antivirals) caused the improvement.

What the Results Show

The patient presented with bilateral (both eyes) dendritiform (tree-like branching) lesions on her corneas that resembled herpes keratitis. However, these lesions stained poorly with fluorescein dye, which is unusual for herpes infections. Advanced imaging revealed the true nature of the problem: multiple crystal-like deposits in the superficial (outer) layer of the cornea. When the patient resumed strict adherence to a low-protein diet and discontinued antiviral therapy, her symptoms improved noticeably. Follow-up imaging confirmed partial regression of the corneal lesions and a decrease in the crystal deposits. This improvement occurred over the course of treatment with dietary management alone, without antiviral medications.

The patient’s photophobia (light sensitivity) and ocular discomfort both decreased with dietary management. The imaging studies showed that the crystal deposits were specifically located in the epithelial layer (outermost layer) of the cornea. The poor staining with fluorescein dye was an important clue that distinguished this condition from typical herpes keratitis, which usually stains more intensely.

Hereditary tyrosinemia type 1 is known to cause various eye problems, including photophobia and corneal involvement. However, the presentation of pseudodendritic lesions that mimic herpes keratitis is rare and not well-documented in medical literature. This case adds to the limited knowledge about how this metabolic disorder affects the cornea and demonstrates that advanced imaging can help differentiate metabolic corneal disease from infectious causes. Previous cases have shown that metabolic control improves ocular symptoms in tyrosinemia, which this case confirms.

This is a single case report involving only one patient, so the findings cannot be applied to all people with hereditary tyrosinemia type 1. The patient had incomplete adherence to her diet before seeking treatment, making it unclear whether the improvement was solely due to dietary management or a combination of factors. The case report does not include a control group or comparison to other patients. Long-term follow-up data beyond the initial improvement period is not provided. The specific duration of symptoms before diagnosis and the exact timeline of improvement are not clearly detailed.

The Bottom Line

For people with hereditary tyrosinemia type 1 who develop eye problems: (1) Ensure strict adherence to a low-protein diet as prescribed by your medical team, as this appears to help control corneal symptoms; (2) If eye symptoms develop, inform your eye doctor about your metabolic condition so they can consider this in their diagnosis; (3) Do not assume that eye lesions resembling herpes are definitely herpes infections—advanced imaging may be needed to confirm the diagnosis. Confidence level: Low to moderate, based on a single case report.

This information is most relevant to: people with hereditary tyrosinemia type 1 who develop eye symptoms; eye doctors and metabolic specialists who care for patients with rare metabolic disorders; family members of people with tyrosinemia who should be aware of potential eye complications. This case is less relevant to people without hereditary tyrosinemia or other metabolic disorders.

In this case, improvement in symptoms and imaging findings was noted after the patient resumed strict dietary adherence, though the exact timeline of improvement is not specified in the report. Realistic expectations would be weeks to months for noticeable improvement, but individual responses may vary.

Want to Apply This Research?

  • If you have hereditary tyrosinemia type 1, track daily protein intake (grams) against your prescribed limit, and rate your eye symptoms (light sensitivity and discomfort) on a scale of 1-10 each day to monitor correlation between dietary adherence and symptom improvement
  • Set daily reminders to follow your prescribed low-protein diet and log each meal in the app. Take weekly photos of your eye comfort level (subjective rating) to create a visual record of improvement over time
  • Maintain a monthly summary view showing protein intake compliance percentage and average eye symptom scores. Share this data with your eye doctor and metabolic specialist at regular appointments to demonstrate how dietary adherence affects your eye health

This case report describes one patient’s experience and should not be used for self-diagnosis or self-treatment. Hereditary tyrosinemia type 1 is a rare condition requiring specialized medical care. If you have this condition and develop eye symptoms, consult with both your eye doctor and metabolic specialist before making any changes to your treatment plan. Do not stop antiviral medications or other prescribed treatments without medical guidance. The findings from a single case cannot be applied to all patients with this condition, as individual responses to treatment vary. Always seek professional medical advice for diagnosis and treatment of eye problems.