Granulomatosis with polyangiitis (GPA), formerly known as Wegener’s granulomatosis, is a necrotizing vasculitis affecting small and medium-sized vessels. It is part of a spectrum of conditions known as antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis [1] . It is a rare condition with an estimated global annual incidence of 10 to 20 cases per million, depending on geographical location [2] .

Clinically, GPA is characterized in its complete form by otorhinolaryngological signs, pulmonary and renal involvement [3] . Ocular involvement is also common in GPA, with various manifestations depending on the different ocular tissues affected, but it mainly causes orbital mass, dacryocystitis, scleritis, conjunctivitis, and keratitis [4] .

GPA remains a real diagnostic challenge, sometimes presenting with atypical symptoms such as eye involvement (scleritis) or systemic infection (candidemia) [5] [6] . A limited form may also occur, although the classic form of GPA involving the kidneys and respiratory tract is more commonly observed [7] .

To illustrate these clinical features, we report an unusual case of GPA manifesting solely as bilateral ocular involvement at the Bogodogo Teaching Hospital in Ouagadougou, Burkina Faso.

A concise timeline of key events to clarify the chronology is as follows:

On day 0, in the right eye, the examination reveals eyelid oedema, diffuse conjunctival hyperaemia with chemosis, a perforated cornea in the upper part with iris herniation, and the retrocorneal structures are not visible. The examination revealed pseudoptosis in the left eye, diffuse conjunctival hyperaemia, three corneal ulcerations, one located in the superotemporal region and two punctiform ulcerations located in the nasal and superior regions, respectively ( Figure 1 ), and an iris hernia ( Figure 2 ). The diagnosis of bilateral peripheral ulcerative keratitis complicated by corneal perforation in the right eye was made. The postoperative course was uneventful. In addition, an internal medicine consultation was requested during hospitalization for the etiological assessment. Upon re-evaluation, the extraocular clinical examination revealed no specific abnormalities. The diagnostic hypotheses considered were infectious causes (syphilis, viral infections: HCV, HIV); systemic causes (rheumatoid arthritis, relapsing polychondritis, systemic vasculitis). Paraclinical tests were prescribed, and the patient was discharged on day 6 pending the results of the etiological tests. Treatment with moxifloxacin eye drops was prescribed for the left eye (1 drop 4 times per day).

On week 4, the patient was seen in internal medicine consultation with the results of the paraclinical assessment. According to the baseline laboratory values, the tests revealed a biological inflammatory syndrome with a C-reactive protein level of 20.15 mg/l, mild anaemia at 12.8 g/dl with hyperleukocytosis at 10.49 G/l, predominantly neutrophils at 67%, and thrombocytosis at 484 G/l. The erythrocyte sedimentation rate (ESR) was not measured. The prescribed immunological assessment was positive for ANCA with anti-PR3 specificity at 182 AU/l (Antibody Unit/litre); rheumatoid factors, ACPA and antinuclear antibodies were negative. Serological tests for HCV, HIV and syphilis were negative.

The differential diagnosis discussion of PUK was excluded:

The assessment was completed by a clinical ENT examination, which was normal (no evidence of sinusitis or recurrent chondritis). Renal function, including creatinine at 81 µmol/l (GFR CKD-EPI = 115.5 ml/min) and urinalysis without proteinuria or haematuria, was normal. The chest X-ray was consistent with bilateral interstitial pneumonia, with no nodules observed. A chest CT scan was considered to rule out occult nodules but was not performed due to financial constraints.

The final diagnosis was ANCA-associated vasculitis of the granulomatosis with polyangiitis type, revealed by bilateral ulcerative keratitis.

In collaboration with ophthalmologists and internists, induction treatment is initiated based on oral corticosteroid therapy with prednisolone 1 mg/kg/day in combination with an immunosuppressant, notably methotrexate at a dosage of 0.3 mg/kg/per week with folic acid supplementation of 10 mg/week. A tapering of corticosteroid therapy is recommended, with a target dose of 5 to 7.5 mg/day at 4 months following induction and withdrawal at one year.

In week 6, the current visual acuity at the latest follow-up shows significant improvement in the left eye (visual acuity at 4/10), with resolution of the biological inflammatory syndrome (C-reactive protein level of 0.57 mg/l) and normalization of haemoglobin and platelets.

The significance of this case report lies in the fact that granulomatosis with polyangiitis can manifest itself simply as bilateral ocular involvement. Furthermore, this ocular involvement can also compromise the visual prognosis in cases of delayed diagnosis.

Granulomatosis with polyangiitis (GPA) is characterized by extravascular necrotizing granulomatous inflammation, usually affecting the respiratory tract. In most cases, the clinical presentation is dominated by a pulmonary-renal syndrome with alveolar haemorrhage and rapidly progressive glomerulonephritis [8] . Other organ damage is also observed. Ocular involvement is common in GPA, with ocular manifestations varying widely and reported in 16% to 78% of cases. In 27% of cases, they are the first sign of undiagnosed GPA [9] .

Corneal involvement is a common ocular manifestation of GPA. It can be primary or secondary. The inflammation characteristic of GPA can specifically affect the cornea, leading to peripheral ulcerative keratitis (PUK) [10] . PUK is generally unilateral and sectoral but can also occur bilaterally in 40% of patients [11] . The collapse of the corneal epithelium makes the corneal stroma thinner and, if keratolysis progresses, it can cause perforation. Matrix metalloproteinases (MMPs) may contribute to the keratolysis observed. PUK in GPA is also linked to the presence of an autoantibody against cytokeratin 3 [12] .

GPA has one essential element for diagnosis and monitoring: the presence of ANCA, with diffuse cytoplasmic fluorescence, directed against PR3 in 75% of cases and much more rarely against myeloperoxidase. They are present in approximately 90% of systemic forms and 50% of localized forms of the disease. They are highly specific and therefore have great diagnostic value. Under certain conditions, in combination with suggestive clinical signs, their presence may be sufficient for diagnosis [3] .

Currently, the combination of glucocorticoids and immunosuppressive agents has changed the prognosis for patients with GPA, with a 5-year survival rate of 95% and a 10-year survival rate of 80% [3] . In secondary progressive or localized forms that require more “aggressive” treatment than cotrimoxazole, the treatment often combines:

GPA is a serious condition that can affect visual prognosis in its purely ocular form. Adequate management requires appropriate technical facilities and multidisciplinary collaboration. This atypical mode of presentation deserves to be reported consistently to raise awareness among clinicians about the early diagnosis of GPA.

The authors would like to express their sincere thanks to the entire medical team of the Department of Internal Medicine, Endocrinology, and Metabolic Diseases at Bogodogo Teaching Hospital for their open collaboration.