[Poppers-associated maculopathy]

Background: Poppers are a common drug belonging to the alkyl nitrite group and in use for several decades. They can be legally purchased for air freshening, but are illegal to buy for inhalation. Abuse is associated with maculopathy and visual loss as a rare side effect.

Method: A case series of 27 male, homosexual patients with poppers abuse presenting to a single eye clinic in Berlin, Germany, is described. Four patients with visual impairment and maculopathy associated with the inhalation of poppers were found.

Results: Four patients experienced subacute visual loss over 2-6 months, one patient can no longer read without a magnifying glass. The median age is 40.25 years (28-45 years). Three patients are HIV-positive (known since 10-22 years, HAART), a patient is also hepatitis C-positive. No other ocular and systemic diseases are known. Poppers have been inhaled for about 1.5, 12, 15 and 25 years (3-4 ×/week); all patients have a mixed use with the brands Jungle Juice, Rush and Amsterdam. Three patients noticed a simultaneous change in colour and shade. Clinical signs on fundoscopy ranged from normal foveal appearance to yellowish, dull macula. Optical coherence tomography (HD-OCT) showed varying degrees of disruption of the presumed inner segment/outer segment (IS/OS) junction; 3 cases bilaterally symmetrical.

Discussion: Although poppers have been in use for several decades, in 2007 in England, the popper composition was changed by law from isobutyl nitrite to isopropyl nitrite. It is hard to distinguish whether a specific nitrite group triggers the maculopathy or whether it is the dose level, thus suggesting the existence of a cumulative dose-response relationship. We postulate that a major factor of the manifestation of maculopathy is the individual limit of vulnerability. Despite decades of use, the majority of our series does not present any pathology. Limits of our patient population represents the HIV disease: three maculopathies of our series are HIV-associated and controlled by antiretroviral therapy, so that a clear distinction to the disease is absent. Poppers were earlier regarded to cause an AIDS-defining disease of viral aetiology: Kaposi sarcoma. We are well aware of that association and postulate that the observed maculopathies are not causally related to HIV disease and antiretroviral therapy. Considering the cultural background of our patients (multiple partners, frequent sex) and the disinhibiting effect of poppers, an increased risk of HIV disease is found. Since this disease is a rare disorder, patients should be asked specifically about poppers abuse. Further study of the effect of poppers on maculopathy is needed.