Introduction 1 1 2 3 DT is a minimally invasive self-standing procedure. It can be used for elective and emergency intervention in patients with subglottic and tracheal stenosis. This has been described elsewhere (G.B. Halmos, F.G. Dikkers, Dilatation tracheoscopy in treatment of subglottic and tracheal stenosis, submitted for publication). Patients suffering from WG present differences (age, sex, response to treatment) compared to other aetiologies, which justifies separate publication. The objective of this study is therefore to evaluate the effect of the treatment of SGS and TS by DT in patients with WG. Methods We retrospectively identified all patients from our institution that underwent a DT between February 2001 and September 2005. The total cohort of benign, grade II (Myer-Cotton) subglottic or tracheal stenosis consisted of patients with a history of posttraumatic tracheal stenosis, thermal tracheal stenosis, posttracheotomy cicatricial stenosis, tracheal rupture, postintubation stenosis, and WG, amongst others. As stated before, the cohort is described elsewhere. 4 5 1 ® Fig. 1 Groningen dilatation tracheoscope  2 3 Fig. 2 Patient nr 9 pre dilatation. During laryngotracheoscopy a subglottic stenosis is clearly visible. The vocal cords can be seen bilaterally  Fig. 3 Patient nr 9 during DT. The dilatation tracheoscope is introduced through the stenosis. Parts of the tissue protrude through the tiny distal openings of the tracheoscope  The constellation of the tracheoscope is suitable for most grade II (Myer-Cotton) subglottic or tracheal stenosis. The intervention can be repeated after any time interval. Typically, no antibiotics or corticosteroids are used. The use of mitomycin-C was considered in each case, but it was never used, because mitomycin-C should be used in fresh wounds. Patients are dismissed the day after DT. Peakflows were measured three times (Respironics Healthscan Inc., Cedar Groove, NJ, USA) in an upright position. The mean of the three measurements was taken. Results Patients 5 4 4 2 1 1 1 Table 1 ANCA PR3 MPO Patient No. Sex Age at presentation of WG Organs involved at first presentation of WG ANCA specificity Number of relapses of WG Organs involved at first relapse of WG Follow-up after diagnosis of WG (years) Age at first presentation of SGS or TS Interval between diagnosis of WG and first treatment of TS or SGS (months) 1 M 44 Joints PR3 12 Joints, skin 17 51 92 2 F 26 Lungs, Trachea PR3 1 Lungs, kidney 14 26 0 3 F 43 Trachea MPO 1 Lungs 12 43 0 4 F 57 Joints PR3 2 Ear, eye, kidney, joints 12 67 122 5 F 26 Trachea PR3 1 Kidney, eye 11 31 60 6 F 51 Mastoid PR3 2 Nose (concha inferior), mastoid 10 58 81 7 F 42 Ear drum Atypical 0 Lung, ear drum 8 45 35 8 F 52 Nose PR3 1 Nose (septum and concha), joints, eye 7 56 48 9 F 33 Nasal vessels PR3 0 Vessels 4 33 2 1 1 2 P P Table 2 Patient characteristics of nine patients with Wegener’s granulomatosis who underwent DT for SGS or TS compared with the reference group of 182 patients who were diagnosed with WG in the same period without evidence of SGS or TS  n n P Male/ female number (%) 1/8 (11%/89%) 104/78 (57%/43%)  <0.01 Age at diagnosis of WG (years, mean ± SD) 41.6 ± 11.2 53.3 ± 17.0 <0.05 ANCA specificity n  n n  n  n  n Not significant WG DT SGS TS ANCA PR3 MPO HNE Follow-up of the DT-group 3 3 4 5 2 3 Table 3 Follow-up after last DT Patient number Location of stenosis Number of DT’s Follow-up after last treatment (months) Tracheotomy required 1 Subglottic 2 19 No 2 Subglottic 2 21 Yes, temporary 3 Trachea 2 43 No 4 Trachea 2 14 No 5 Cricoid 8 12 Yes 6 Subglottic 2 16 No 7 Subglottic 1 54 No 8 Subglottic 1 26 No 9 Subglottic 2 24 No Fig. 4 Patient nr 6 with acute WG during biopsy of a subglottic stenosis  Fig. 5 Patient nr 6 after pulse therapy and intubation. The picture was taken one week after Fig. 4  6 Fig. 6 arrows  Discussion There are multiple causes of benign laryngeal or tracheal stenosis, the most common being traumatic. However, if there is no prior history of tracheal trauma, the aetiology of the stenosis may be obscure and difficult to determine, necessitating a systematic approach to make the diagnosis. Excluding trauma, the differential diagnosis of TS can be subdivided into four categories: congenital, neoplastic, infectious, and inflammatory. Congenital TS is really quite rare and is often the result of posterior fusion of the tracheal rings, thereby forming complete rings. Other causes of congenital stenosis include vascular rings and other congenital cardiovascular anomalies such as an anomalous subclavian artery. These patients typically present at young age. Primary benign tumours of the trachea such as chondromas, fibromas, squamous papillomas, hemangiomas, and granular cell tumours are also unusual causes of stenosis. In addition, extrinsic compression of the trachea can occur by thyroid neoplasms and goiters. A number of infections of the bronchopulmonary tree can lead to TS. Fungal infections such as histoplasmosis and blastomycosis should always be considered when the aetiology of the stenosis is unclear. Serologic testing and histopathologic examination can be helpful in this regard. Other infectious causes of TS include rhinoscleroma, tuberculosis, syphilis, and diphtheria. Non-infectious, inflammatory causes of TS include sclerosing mediastinitis, primary amyloidosis, and sarcoidosis. WG and relapsing polychondritis can also cause TS, but they are almost always seen in combination with other, more classic hallmarks of these diseases. A laryngeal or tracheal stenosis is optimally diagnosed via tracheal visualization, which is generally performed by an otorhinolaryngologist. Indirect and fiberoptic laryngoscopy are non-invasive examination techniques that can be performed in the office, but usually do not show the entire trachea. A subglottic stenosis is not always visible, therefore direct rigid tracheoscopy in general anaesthesia is indicated in cases suspect of WG. 6 2 7 8 Another particular finding is that eight of our nine patients were female. This contrasts significantly with the male/female ratio in the reference group that consisted of WG patients that were diagnosed in the same period as the DT group but who did not have evidence of SGS or TS. It is difficult to speculate on the reason for this female preponderance. Anatomically the female airway is narrower than the male, making it more prone for post-intubation stenosis. However, we even had females presenting with a SGS or TS. More research in larger series has to be performed to explain this phenomenon. 9 9 10 All patients had involvement of additional organs. In three patients the disease presented as a stenosis, and laryngotracheoscopy revealed the size and site of the lesion. Organs involved showed no pattern in which there should be additional suspicion for the development of SGS or TS. There was no relation between the number of relapses and the development of TS or SGS. The TS or SGS occurred more often in periods where the disease appeared to be less active. Remarkably, TS or SGS predominantly became manifest in periods in which WG appeared to be inactive. Interestingly, seven out of our nine patients who developed TS or SGS had not been diagnosed previously with tracheal involvement of WG, neither at first presentation nor at relapse(s). We speculate that during active disease a subclinical tracheal involvement occurs which may subsequently heal with scar formation. To examine this hypothesis in patients, elective tracheoscopy should be performed in all patients with WG. The time interval between presentation of clinical stenosis in these seven patients (mean 63 months, median 60, range 2–122) favours watchful waiting. DT with the Groningen dilatation tracheoscope is a safe, minimally invasive procedure for the treatment of Cotton-Myer grade II subglottic or tracheal stenosis of various origin. It is an elegant, self-standing surgical intervention, where no additional interventions are needed. For an overview of the effect of DT the reader is referred elsewhere (G.B. Halmos, F.G. Dikkers, Dilatation tracheoscopy in treatment of subglottic and tracheal stenosis, submitted for publication). 11 x y We have registered no complications or deaths during or because of DT. We have three reasons to regard dilatation tracheoscopy as a minimally invasive intervention. We have experienced no complications related to dilatation tracheoscopy. It requires short hospitalization (generally 3 days). The intervention is not straining for the patients. 12 13 3 14 9 Conclusion WG as such is a rare disease, and SGS and TS are rare symptoms in patients with WG. DT can offer a simple and repeatable solution to this very serious symptom. Patient complaints and monitoring of peakflow values offer simple tools for the decision whether or not to intervene. However, a causative solution to WG should be the ultimate goal.