Epitheliopathy, Acute Posterior Multifocal Placoid Pigment

 Epitheliopathy, Acute Posterior Multifocal Placoid Pigment

DISEASE OVERVIEW

Acute posterior multifocal placoid pigment epitheliopathy (APMPPE) is a rare eye disorder of unknown (idiopathic) cause. The disorder is characterized by the impairment of central vision in one eye (unilateral) but, within a few days, the second eye may also become affected (bilateral). In most cases, the disorder resolves within a few weeks without loss of clearness of vision (acuity). However, in some cases, visual acuity does not improve. This disorder occurs predominantly in young adults, with a mean age of onset of 27 years. It is reported that, in approximately one-third of the cases, an influenza-like illness preceded the development of the disorder.

SIGNS & SYMPTOMS

Prior to the onset of disease, about 33% of patients present with flu-like or viral symptoms such as fever, swollen lymph glands, nausea, vomiting, joint pain and/or tenderness. Moderate to severe headaches may also be present and, much more rarely, there may be neurological signs such as temporary loss of speech (aphasia) and/or weakness of the arms and legs.

In the early stages of APMPPE, patients notice areas of visual blotchiness within the field of clear vision (blotchy scotomata), flashes of light (photopsia) caused by irritation of the retina, distortion of the shapes of objects (metamorphopsia), increased sensitivity to light (photophobia) and conjunctivitis.

During the late stages of the disorder, patients usually notice mild decreases in vision. Rarely, the impaired vision may be severe.

Examination of the eye usually shows multiple flat, yellow-white lesions of the posterior pole of the nerve-rich membrane lining the eyes (retina). Frequently the veins of the retina are inflamed (vasculitis), but the inflammation often subsides without treatment. In some cases, pigment changes in the retina may be permanent and the resulting visual impairment may also be permanent. However, in most cases the disorder is characterized by a temporary impairment of vision.

CAUSES

The exact cause of acute posterior multifocal placoid pigment epitheliopathy is not known. Researchers suspect that it may be caused by a virus. It can subside without treatment or it may recur at any time. The viruses may stay dormant in humans for extended periods of time, then for reasons yet unknown may unexplainably become reactivated.

DISORDERS WITH SIMILAR SYMPTOMS

Symptoms of the following disorders can be similar to those of acute posterior multifocal placoid pigment epitheliopathy. Comparison may be useful for a differential diagnosis:

Diffuse unilateral subacute neuroretinitis (DUSN) is a progressive parasitic disease affecting the outer retina and retinal pigment epithelium (RPE). This syndrome is primarily unilateral, although bilateral cases have occurred. Examination of the eye shows visual loss, vitreous cells, optic disc inflammation and leakage, and transient, but recurrent, crops of gray-white outer retinal lesions.

Stationary or migrating parasitic worms (nematodes) have been identified deep in the retina or in the subretinal space. Later in the course of the disease, slowly progressive RPE changes and optic atrophy may be observed, as well as narrowing of the retinal vessels.

Multifocal choroidopathy syndromes are a group of rare disorders involving a major pathological change at or near the level of the retinal pigment epithelium (RPE) with or without inflammation of the blood vessels in the choroid layer of the eye. The cause is unclear but is thought to be either an obstruction of the blood vessels feeding the choroid layer or, possibly, an immunologic response directed at the RPE itself. Many clinical features of these individual entities overlap, causing much confusion. Whether these conditions represent distinct entities or whether some may be parts of a spectrum of the same basic disease is still unknown.

Retinitis pigmentosa (RP) is one of a group of inherited diseases causing degeneration of the retina. When the retina degenerates, as in retinitis pigmentosa, the vision decreases and may occasionally be lost. One of the earliest symptoms is difficulty seeing at night or in dimly lit places. This is slowly followed by tunnel vision. The rate and extent of progression is extremely variable, but RP does not occur with the sudden onset of APMPPE. (For more information on this disorder, choose “Retinitis Pigmentosa” as your search term in the Rare Disease Database.)

Serpiginous choroiditis, also called geographic helicoid peripapillary choroidopathy, is a rare, inflammatory disease of unknown cause (idiopathic) affecting the inner choroid and retinal pigment epithelium. Typically serpiginous choroiditis occurs bilaterally and is almost always progressive. Though longstanding remissions can be achieved through aggressive immunosuppressive therapy, patients not receiving such therapy often suffer through multiple flare-ups and are often left with macular scarring and significant visual loss.

The white dot syndromes are a group of idiopathic multifocal inflammatory conditions involving the retina and the choroid. They are characterized by the appearance of white dots in the fundus. The diseases that constitute the white dot syndromes include acute posterior multifocal placoid pigment epitheliopathy (APMPPE), serpiginous choroiditis, multiple evanescent white dot syndrome (MEWDS), multifocal choroiditis and panuveitis (MCP), punctate inner choroidopathy (PIC), and diffuse subretinal fibrosis (DSF). Presumed ocular histoplasmosis syndrome (POHS) and birdshot retinochoroidopathy are additional white dot syndromes.

STANDARD THERAPIES

Treatment of acute posterior multifocal placoid pigment epitheliopathy is symptomatic and supportive. Very often vision returns without specific treatment.

TYPE OF DOCTOR AND DEPARTMENT: EYE SPECIALIST CAN DIAGNOSE THIS DISEASE.