The legend for Figure 3 in this article states 'Corneal Staining with flourescein'. in fact the picture actually shows conjunctival staining with Rose Bengal.

As mentioned in the article, Rose Bengal can be used to indicate dead and dying tissue however it is used much less these days. One reason for this is that it causes considerable stinging on application - especially in those with very dry eyes.

There are some other errors in the article that could potentially confuse the primary care physician. The authors state 'The diagnostic approach for GPs starts by discarding other causes of dry eyes (allergic conjunctivitis, blepharitis, rosacea)'. Aside from the wisdom of 'discarding' diagnoses, none of these conditions cause dry eyes per se. Allergic conjunctivitis sufferers typically complain of itchy eyes but this is not caused by drying. Blepharitis causes gritty, burning eyes because of meibomian dysfunction - tear film evaporation is often accelerated but the eyes are not primarily dry. Moreover, the conditions mentioned are every common and can coincidentally occur in patients with Sjogrens syndrome.

As with so many conditions simple history taking is the real key to the diagnosis. Patients with irritable, uncomfortable eyes who also have a dry mouth should have Sjogrens syndrome ruled out. Significant discomfort that is worse after concentration (eg reading or watching TV) which reduces the blink rate suggests excessive drying as does a good response to tear film supplements. These symptoms in themselves do not make the diagnosis of Sjogrens as idiopathic dry eye is far more common.

Competing interests: None declared