Pathology of the Head and Neck

Larynx and Hypopharynx Chapter 7 205Laryngeal involvement in RA includes arthritis of thecricoarytenoid and cricothyroid joints, and/or the formationof rheumatoid nodules in the soft tissue of thelarynx [47, 95, 130].Histologically, the acute phase of arthritis is characterisedby swelling and thickening of the synovia, whichis heavily infiltrated by mononuclear cells, resulting invillous hypertrophy. In the chronic phase, there is destructionof the articular cartilage and proliferation offibrous tissue with obliteration of the joint spaces, rarelyleading to bony ankylosis [47].Rheumatoid nodules may develop in the soft tissueadjacent to the joints, or in the vocal cords. Microscopically,they consist of a central fibrinoid necrosis, surroundedby palisading macrophages, lymphocytes andplasma cells (Fig. 7.4) [95, 343].In the acute phase symptoms and signs are usuallymild, and consist of pain and voice disturbance. In thechronic phase, dyspnoea and respiratory obstructionmay develop [2, 39, 95].Arthritis and rheumatoid nodules are not pathognomonicof RA, but are also seen in patients with other autoimmunediseases, particularly systemic lupus erythematosus[241, 366].Rheumatoid arthritis is treated by anti-inflammatorydrugs and local administration of steroids by meansof injection or aerosol; in rare cases, surgical therapy isneeded to relieve airway obstruction [2, 27, 39, 95].7.3.3.4 Relapsing PolychondritisRelapsing polychondritis (RP) is a rare autoimmunedisease characterised by progressive inflammationof cartilaginous structures, both elastic and hyaline,throughout the body [68, 233, 364]. The disease typicallyinvolves the ear, nose, eye, larynx and lower respiratorytract, costal cartilages, joints, cardiovascularsystem, renal tissue and central nervous system. Themost serious consequence of RP in the larynx and tracheais destruction of the cartilaginous framework,with collapse of the airway and breathing difficulties.RP commonly affects patients between 40 and 60 years[208], and a female-to-male ratio of 3:1 was recentlynoted [364]. Aetiologically, there is strong indication ofan autoimmune origin of RP [364], which has recentlybeen supported by the finding of antibodies to type IIcollagen in two-thirds of patients [349], and linkage tothe human leukocyte antigen DR4 gene and other autoimmunediseases. The onset of RP is generally sudden,with recurrent attacks of acute inflammation ofthe auricle. The diagnosis of RP is believed to be convincingif patients have at least three of the followinginvolvements: bilateral auricular lesions, seronegativearthritis, nasal and ocular affections, respiratory tractFig. 7.4. Rheumatoid nodule of the vocal cord. Fibrinoid necrosissurrounded by palisading macrophages, lymphocytes and plasmacellschondritis, audiovestibular damages and histologicalconfirmation of the disease [233].Hoarseness, coughing, dyspnoea, choking and tendernessover the laryngotracheal cartilages are symptomsof laryngeal and lower respiratory tract involvement[152]. Although airway obstruction could be localisedto the glottic and subglottic area, a diffuse involvementof the respiratory tract is more common [247]and occurs in up to 50% of patients with RP [93].Histologically, the affected cartilage shows distinctfeatures: the cartilaginous matrix loses its basophilicstaining, peri-and intracartilaginous inflammation isevident, inflammatory cells infiltrate the perichondriumand cartilage. The chondrocytes become vacuolatedand necrotic, and fragmentation of cartilage is evident.With the progression of the disease, necrotic cartilageis replaced by granulation tissue and later by fibrosis.In the course of the disease, persistent inflammationcan destroy the cartilaginous rings and cause luminalcollapse.Differential diagnosis includes all conditions that essentiallyshow cartilage destruction: various infectious(tuberculosis and other bacterial, fungal, and viral infections),non-infectious diseases (sarcoidosis, Wegener’sgranulomatosis and other types of systemic vasculitides)and tumours (lymphoma, cartilaginous tumours).Treatment for RP is based on systemic steroid and occasionallyimmunosuppressive therapy [261]. Involvementof the larynx and the lower respiratory tract is themost serious complication. The mortality rate reported