What could cause a black painful dot in the outer corner of the eye in a patient with a history of severe side effects to fluconazole (an antifungal medication)?

Black Painful Dot in the Outer Corner of the Eye

This presentation most likely represents either a fungal infection (particularly Candida endophthalmitis given your fluconazole intolerance history), a localized hemorrhage, a foreign body, or a pigmented lesion—and requires immediate ophthalmologic examination with dilated retinal exam to rule out sight-threatening infection.

Immediate Diagnostic Approach

You need an urgent ophthalmologic evaluation within 24 hours to determine the exact nature of this lesion, as fungal endophthalmitis can cause irreversible vision loss if not treated promptly 1. The ophthalmologist should perform:

• Dilated retinal examination to visualize the posterior segment and assess for chorioretinitis or endophthalmitis 1, 2
• Slit-lamp examination to evaluate the anterior chamber and rule out keratitis 1
• Diagnostic vitreal aspirate if endophthalmitis is suspected, to obtain culture and direct microscopy 1

Most Concerning Diagnosis: Fungal Eye Infection

Given your history of severe fluconazole side effects, if you previously had systemic candidiasis or candidemia, you may be at risk for Candida endophthalmitis, which can present as:

• Dark lesions in the eye (chorioretinal lesions appear as white-yellow fluffy lesions initially, but can appear darker with hemorrhage or pigmentation) 1
• Pain and visual disturbance 2
• Inflammation that may be initially asymptomatic but progresses to threaten vision 2

Up to 16% of patients with candidemia develop ocular involvement, often without initial symptoms 2.

Treatment Options for Fluconazole-Intolerant Patients

If fungal endophthalmitis is confirmed, you have excellent alternatives to fluconazole:

For Severe or Advancing Lesions:

• Amphotericin B deoxycholate 0.7-1 mg/kg daily combined with flucytosine 25 mg/kg four times daily is the gold standard for advancing lesions or those threatening the macula 1
• Liposomal amphotericin B 3-5 mg/kg daily provides effective alternative therapy with better tolerability 2

For Less Severe Disease:

• Voriconazole represents an excellent alternative with superior ocular penetration at 6 mg/kg IV twice daily for 2 doses, then 3-4 mg/kg twice daily 1, 2
• Voriconazole achieves excellent intravitreal levels and can also be given topically 1

Surgical Intervention:

• Partial vitrectomy with intravitreal amphotericin B is strongly recommended for severe endophthalmitis with vitreitis and can be sight-saving 1
• Early surgical intervention is crucial in advanced cases 1

Duration:

• At least 4-6 weeks of treatment, determined by stabilization or resolution of lesions on repeated ophthalmologic examinations 1

Alternative Non-Infectious Causes

The black painful dot could also represent:

• Subconjunctival or subretinal hemorrhage (appears dark red to black)
• Foreign body embedded in the conjunctiva or sclera
• Pigmented nevus or melanoma (though typically painless unless inflamed)
• Aspergillus keratitis if there's corneal involvement—this is excruciatingly painful and requires emergency ophthalmologic intervention with topical and systemic antifungal therapy 1

Critical Pitfalls to Avoid

• Do not delay ophthalmologic evaluation—fungal endophthalmitis progresses rapidly and can cause irreversible vision loss 1
• Do not assume this is benign without proper examination, especially given your antifungal medication history 2
• Do not use fluconazole given your documented severe side effects—multiple effective alternatives exist 2, 3
• Echinocandins have poor ocular penetration and should be avoided for eye infections despite their effectiveness for systemic candidiasis 1

Next Steps

1. Schedule emergency ophthalmology appointment today for dilated examination 1, 2
2. If fungal infection is confirmed, initiate systemic antifungal therapy immediately with amphotericin B or voriconazole 1, 2
3. Consider diagnostic vitreal aspirate if endophthalmitis is suspected 1
4. Discuss surgical intervention with ophthalmologist if severe disease is present 1