Phrenic Nerve Conduction Study in the Early Stage of Guillain-Barre Syndrome as a Predictor of Respiratory Failure

BACKGROUND

Guillain-Barré syndrome (GBS) has unpredictable clinical course with severe complication of respiratory failure.

OBJECTIVE

To identify clinical profiles and electrophysiological study particularly non-invasive Phrenic nerve conduction study in patients of early GBS to predict respiratory failure.

METHODS

64 adult (age≥18yrs) patients of early GBS (onset ≤ 14 days) during the study period from January 2014 to October 2015 were evaluated by clinical profiles of age, gender, antecedent infection, time to peak disability, single breath counts, cranial nerve involvement, autonomic dysfunction and non-invasive Phrenic nerve conduction study. Patients with predisposition factors of polyneuropathy like diabetes mellitus, hypothyroidism, vitamin deficiency, renal failure were excluded.

RESULTS

Among 64 patients abnormal phrenic nerve conduction study was seen in 65.62% cases (42/64) and 45.23% (19/42) of them developed respiratory failure. Phrenic nerve sum latency, amplitude, duration and area were abnormal in those who developed respiratory failure and they had sum of phrenic nerve latency >28 msec, sum of CMAP amplitude <300 μV, sum of CMAP duration >50 msec and sum of area < 4 mVmS. None with normal phrenic nerve study developed respiratory failure. It was found that age, gender, preceding infection, autonomic involvement and types of GB syndrome had no influence on development of respiratory failure (p>0.05). Rapid disease progression to peak disability, more severe disease, shorter single breath counts and cranial nerve involvement were seen more often in patients with respiratory failure.

CONCLUSION

Abnormal Phrenic nerve conduction study in the early Guillain-Barré syndrome might be of great value independently in predicting impending respiratory failure.

Unusual Cause of Spontaneous Bilateral Pneumothorax Secondary to Osteosarcoma Metastasis

Spontaneous pneumothorax is an emergency situation and early diagnosis and management is very important. Pneumothorax is rarely the first manifestation of lung metastasis. Spontaneous pneumothoraxes have been reported in some osteosarcoma patients. We hereby report a case of a bilateral spontaneous pneumothorax, revealing metastasis of an osteosarcoma.

Dystrophic and psammomatous calcifications in a desmoid tumor. A light microscopic and ultrastructural study

A desmoid tumor occurring in the abdominal wall of a 6-year-old boy with extensive microcalcifications was documented. Two forms of calcifications were observed: an irregular, amorphous dystrophic calcification of the collagen fibers and an organized, laminated psammomatous calcification (psammoma bodies). Ultrastructural studies revealed that the dystrophic calcification is a result of direct mineralization of individual collagen fibrils with subsequent coalescence to form large, calcified masses. Psammomatous calcification tended to cluster around areas where the collagen fibers assumed a whorled configuration. It is suggested that the circular orientation of the collagen fibers in some way favors the laminar deposition of hydroxyapitite crystals. The cause of the pathologic calcifications is the presence of extensive amorphous eosinophilic degeneration of the collagen fibers.