Angela Zhu, MD, is an Ophthalmologist and Clinical Assistant Professor, Pediatric & Adult Cornea/Cataract/External Diseases, at Bascom Palmer Eye Institute in Miami. In this interview with
CheckRare, Dr. Zhu describes some of the key features of plasminogen deficiency and why ophthalmologists are often the healthcare providers who begin the process toward diagnosis.
Plasminogen deficiency type 1 (PLGD-1) is a rare genetic disorder in which the body fails to make adequate quantities of plasminogen, the molecule responsible for protection against abnormal fibrin clotting. It generally manifests initially (in about 80%) as ligneous conjunctivitis, in which thick membraneous lesions (from from fibrin accumulation) develop on the surface of the eye and in the eyelid. As a result, Dr. Zhu said, ophthalmologists are usually the first healthcare provider to see the patient and start the diagnostic journey.
Even though the ligneous lesions on the eye are generally the first symptom in young patients, PLGD-1 can present in many different ways (and in virtually any organ system with mucous membranes). However, fibrin accumulations in internal organs or tissue may be harder to detect.
The diagnosis may not be obvious, especially if the telltale ophthalmologic sign is misread as common infectious conjunctivitis. Patients with PLGD1 can have multiple other symptoms that wax and wane, said Dr. Zhu, and “we need to educate providers about the disease and how it can present. It is underdiagnosed and underrecognized.”
In patients with ligneous conjunctivitis, these fibrous lesions can first be mistaken for discharge, which is common in infectious conjunctivitis. But it doesn’t respond to treatment, unlike viral or bacterial causes of conjunctivitis would. Once the ligneous lesion is removed from the eye, because the plasminogen deficiency is not remedied, it will likely form again.
In the case of these eye lesions or conjunctivitis that doesn’t resolve with antiallergy, steroidal, or antiviral treatment, or grow back after removal, Dr. Zhu stated that laboratory testing for plasminogen activity and antigen testing should be the next step. It will diagnose the condition. “But it could take months before a provider makes the connection [that PLGD1 is the cause].”
The extravascular, fibrin-rich lesions that appear anywhere there is mucous membranes can cause serious or even life-threatening complications. For example, the growths could cause airway obstruction, renal failure if the kidney is involved, chronic hearing loss, or blindness.
“Prior to 2023, we didn’t have an FDA-approved treatment,” she noted. Fresh frozen plasma infusions, which had low plasminogen concentrations, were the mainstay. In 2023, the FDA approved a human-derived plasminogen infusion, which effectively raises plasminogen blood concentrations and ensures adequate plasminogen activity. Plasminogen infusions must be given every two to four days. Five years after initializing therapy, patients have remained free of new lesions, said Dr. Zhu.
The adverse events associated with the infusion include infusion-site reactions, bloating, nausea, and fatigue. She also related that there is a theoretical risk for introduction of infection (as it is a blood product). The fibrin-rich growths can suddenly slough off with therapy, and this could potentially cause unique problems (e.g., a sizeable lesion in the airway breaking off) or bleeding.
CHAPTERS
Introduction 00:00
Plasminogen Deficiency Type 1 Overview 00:56
Diagnostic Odyssey 2:36
Disease Complications 6:08
0
Key Features of PLGD-1
CheckRare 13 hours ago