Plasma cortisol levels in Guillain-Barré syndrome.

OBJECTIVE: To assess the relationship between plasma cortisol level and Guillain-Barré syndrome-related complications, notably respiratory failure. One third of patients with Guillain-Barré syndrome develop respiratory failure, which is predicted by few early indicators. Adrenal function has rarely been studied in Guillain-Barré syndrome. DESIGN: Prospective study. SETTING: Intensive care unit in a teaching hospital. PATIENTS: Patients with Guillain-Barré syndrome referred to our unit (n = 102). INTERVENTIONS: Plasma cortisol levels were measured before baseline and 60 mins after corticotrophin test in 93 patients with Guillain-Barré syndrome at admission, 16 (17%) of whom were ventilated within 24 hrs from admission, 17 (18%) ventilated after the 24th hr and 60 (65%) never ventilated. MEASUREMENTS AND MAIN RESULTS: Mean plasma cortisol levels at baseline and 60 mins after corticotrophin test were 22.9 +/- 11.3 ng/mL and 45.4 +/- 16.1 ng/mL. At baseline, the plasma cortisol levels were significantly higher in 17 (18%) patients, who developed respiratory failure at least 24 hrs later (28.5 +/- 12.1 ng/mL vs. 20.4 +/- 9.6 ng/mL; p = .003) and dysautonomia (33.1 +/- 14.3 ng/mL vs. 21.4 +/- 10.2 ng/mL, p = .003). When adjusting on only validated clinical predictors (i.e., delay between onset and admission <7 days, inability to lift head and vital capacity <60%), baseline cortisol level was the only independent risk factor for respiratory failure (odds ratio: 2.45 per 10 ng/mL [1.23-4.88 ng/mL], p = .01). Fifty-nine patients underwent electrophysiological testing. When adjusting on a validated electrophysiological model (i.e., peroneal proximal/distal compound muscle action potential ratio and vital capacity), baseline cortisol level remained an independent predictor (odds ratio: 2.50 per 10 ng/mL [1.14-5.51 ng/mL], p = .02). CONCLUSION: Measurement of baseline plasma cortisol levels can be helpful for early detection of patients with Guillain-Barré syndrome at risk for respiratory failure at least 24 hrs later.

[Osteoarticular infection diagnosis]. / Moyens diagnostiques des infections ostéo-articulaires.

Diagnosis of osteitis/arthritis requires clinical, microbiological and radiological data. Good quality samples must be obtained before antibiotic therapy is introduced to identify causative microorganisms. New technical methods such as PCR can improve the diagnosis. X-ray radiograph is always performed when osteitis is suspected, even if the diagnosis can be difficult since abnormalities are present late in the course of the disease. MRI is the best method to establish the diagnosis of osteitis or arthritis. Scintigraphy can be an interesting investigation since it can be promptly performed even in patients with foreign material. New technical such as PET-Scan could be interesting to establish the diagnosis. Collaboration between clinicians, microbiologists and radiologists is essential to establish the diagnosis in order to target the appropriate treatment and to improve the prognosis.