Sinonasal manifestations in GPA vary with disease activity: Study
Single-center study looked at changes over time
Sinonasal manifestations — those encompassing the nose and the paranasal sinuses, or the air-filled cavities around the nose — in granulomatosis with polyangiitis (GPA) vary among patients, based on disease activity and duration.
That’s according to a small, retrospective study of GPA patients with sinonasal manifestations seen at a single center in Japan.
Most nasal manifestations observed at diagnosis eased with treatment, while most sinonasal CT findings remained unchanged. The study also found that despite treatment, patients may develop new nasal abnormalities during the disease’s clinical course.
“These findings will be helpful in diagnosis and follow-up of GPA,” the researchers wrote.
The study, “Sinonasal manifestations of granulomatosis with polyangiitis: A retrospective analysis,” was published in the journal Auris Nasus Larynx.
Analyzing sinonasal manifestations over time
ANCA-associated vasculitis (AAV) comprises a group of autoimmune diseases marked by inflammation and damage to small blood vessels in the body that’s typically associated with the production of self-reactive antibodies called ANCAs.
It has three types: microscopic polyangiitis, GPA, and eosinophilic granulomatosis with polyangiitis. “Of these three diseases, otolaryngologists most frequently encounter GPA during patients’ first visit with ear and nasal symptoms,” the researchers wrote. Otolaryngologists are physicians specializing in conditions affecting the ear, nose, and throat and related parts of the head and neck.
Most studies reporting GPA-associated sinonasal manifestations have focused on findings at the time of diagnosis, and none has analyzed changes in these manifestations over time for each patient.
To fill this knowledge gap, a team of researchers at Oita University’s department of otolaryngology and head and neck surgery retrospectively analyzed data from GPA patients who were followed at their department between January 2005 and December 2020.
Of the 37 GPA patients, 17 (45.9%) presented with sinonasal manifestations, and these were included in the analysis.
Their mean age was 63, and 13 (76.5%) were women. The majority (76.5%) had lung involvement, 41.1% had kidney involvement, and only 17.6% had ear, nose, and throat involvement.
More than half of the 17 patients with sinonasal manifestations (58.8%) had ANCAs targeting the proteinase 3 (PR3) enzyme, while five patients (29.4%) were positive for ANCAs targeting the myeloperoxidase (MPO) enzyme. PR3 and MPO are the two most common targets of AAV-driving ANCAs. The remaining two patients (11.8%) were negative for both of these ANCAs.
The most common symptoms at a first consultation were nasal bleeding (29.4%) and nasal obstruction (23.5%), followed by thick, opaque, and colored nasal discharge and a decreased sense of smell (17.6% each). Eyelid swelling was reported in two patients (11.8 %) and cheek pain in one (5.9%).
The most frequent findings upon nose examination were granulation tissue, or new tissue that forms during tissue healing (52.9%) and crusting (47.1%). These were followed by redness of the nasal mucosa, the moist tissue layer that lines the nasal cavity (seen in 29.4%); a form of cell death called necrosis (23.5%); and pus-containing discharge (23.5%). All these symptoms except crusting were eased after treatment initiation.
Structural abnormalities — collapsed nasal bridge, loss of the bony structure that warms and humidifies air (loss of turbinate), and nasal septum perforation — were each present in three patients at diagnosis. These remained unchanged with treatment, and were found in two additional patients during follow-up.
Most abnormalities unchanged after treatment
At the time of diagnosis, CT scans of the sinuses showed that all but one patient (94.1%) had thickening of the mucosa layer, and most (70.6%) had bone thickening. Among more severe findings, bone destruction was seen in four patients (23.5%), and a mass invading the membrane around the eye socket, or orbit, was reported in three cases (17.6%).
Most of these abnormalities remained unchanged with treatment. However, mucosal thickening of the sinuses was eased in three patients, orbital mass was lessened in all three patients, and bone thickening worsened in one patient and was newly developed in two additional patients.
The most commonly affected sinuses were the maxillary sinus, which is located in the cheek area on each side of the nose (94.1%), and the ethmoid sinus, which sits between the nose and eyes (76.5%).
Notably, “destructive nasal findings on CT, such as bone destruction, orbital invasion, and turbinate loss, were specific to PR3-ANCA-positive patients in our cases,” the team wrote.
Nasal tissue samples were available for 13 patients. Inflammatory cell infiltration was detected in all samples, granulation tissue in 10 (76.9%), and necrosis in six (46.2%). Blood vessel inflammation was seen in four (30.8%).
“Our study revealed that mucosal thickening, bone thickening, bone destruction, and orbital invasion mass were major CT findings in patients with GPA,” the researchers wrote. “Intranasal findings such as granulations, crusting, and necrosis were seen in the active phase,” while structural abnormalities “were subsequently seen in the course of the disease,” they added.
The results showed that sinonasal manifestations of GPA “vary depending on the stage and duration of the disease,” the researchers concluded.