A 28‐year‐old Asian woman presented with transient obscuration of her vision. She had no other eye symptoms, central nervous system or systemic symptoms. She had no history of fevers or night sweats. There were no respiratory symptoms. There was no past medical history. She had lived in the United Kingdom for 18
months and had an apparently normal chest X‐ray in her home country before leaving to come to the United Kingdom. She was a non‐smoker with no significant family history of illness.
On examination she was thin but she did not report significant weight loss. There were small lymph nodes in her left cervical chain. Fundoscopy revealed CRVO (see fig 1). Initial investigations showed normal urea and electrolytes, white cell count of 6.4 109 cells/l, haemoglobin 12.2 g/dl, platelets 318, normal clotting screen, C‐reactive protein 3.6 mg/l, erythrocyte sedimentation rate 38 mm/hour, total protein was elevated at 87 g/l, plasma viscosity was elevated at 1.95 pa/s, IgG was 20.51 g/l. She had negative results for the following: rheumatoid factor, anti‐nuclear antibody, lupus anti‐coagulant, IgG and IgM phospholipid antibody, neutrophil cytoplasmic antibody (both anti‐proteinase cytoplasmic and myeloperoxidase perinuclear antineutrophil cytoplasmic antibody), and cryoglobulins. Complement C3 and C4 levels were normal.
Chest X‐ray showed very faint inflammatory shadowing in the left apex and a bulge in the contour of the right hilum possibly representing lymphadenopathy. She had a normal magnetic resonance imaging brain scan. A computed tomography scan of the abdomen and thorax (fig 2) was performed that showed significant lymphadenopathy in the cervical and supraclavicar region as well the right hilum, subcarinal and paratracheal regions. The subcarinal lymph nodes were heavily calcified. There were ‘tree in bud' opacities in the apical segments of the upper lobes, suggestive of active pulmonary tuberculosis.
She had a bronchoscopy as she was unable to expectorate sputum. Bronchoscopic washings of the upper lobes showed scanty acid‐fast bacilli. Fully sensitive Mycobacterium tuberculosis grew from the culture. This confirmed the diagnosis, central retinal vein thrombosis associated with active tuberculosis. She has made a full recovery on quadruple antituberculous therapy, with resolution of her eye symptoms.
Learning points
- Any cause of central retinal vein thrombosis should be followed up and a medical cause sought, a chest X‐ray being an appropriate baseline investigation.
- Early recognition of this association is vital to limit morbidity.
- Tuberculosis can present in a variety of ways and should be thought of in the differential diagnosis especially in recent immigrants to the United Kingdom.
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Image of left retina showing central retinal vein occlusion and retinal haemorrhage.