Chronic sinusitis and the yellow nail syndrome. Diagnosing syndromes that include chronic sinusitis can expedite the management of both conditions. Yellow nail syndrome is usually described as the combination of yellow nails, lymphoedema and often respiratory manifestations such as chronic sinusitis, bronchiectasis and pleural effusions. The pathology responsible for the syndrome is believed to be lymphatic hypoplasia. Diagnosis of yellow nail syndrome is clinical not requiring any specialized tests. In the two cases described, the respiratory tract manifestations required the most active investigation and management. The significance of this syndrome to the otolaryngologist is discussed. 