The wide spectrum of clinical manifestations in Sjögren's syndrome-associated neuropathy.

We assessed the clinicopathological features of 92 patients with primary Sjögren's syndrome-associated neuropathy (76 women, 16 men, 54.7 years, age at onset). The majority of patients (93%) were diagnosed with Sjögren's syndrome after neuropathic symptoms appeared. We classified these patients into seven forms of neuropathy: sensory ataxic neuropathy (n = 36), painful sensory neuropathy without sensory ataxia (n = 18), multiple mononeuropathy (n = 11), multiple cranial neuropathy (n = 5), trigeminal neuropathy (n = 15), autonomic neuropathy (n = 3) and radiculoneuropathy (n = 4), based on the predominant neuropathic symptoms. Acute or subacute onset was seen more frequently in multiple mononeuropathy and multiple cranial neuropathy, whereas chronic progression was predominant in other forms of neuropathy. Sensory symptoms without substantial motor involvement were seen predominantly in sensory ataxic, painful sensory, trigeminal and autonomic neuropathy, although the affected sensory modalities and distribution pattern varied. In contrast, motor weakness and muscle atrophy were observed in multiple mononeuropathy, multiple cranial neuropathy and radiculoneuropathy. Autonomic symptoms were often seen in all forms of neuropathy. Abnormal pupils and orthostatic hypotension were particularly frequent in sensory ataxic, painful, trigeminal and autonomic neuropathy. Unelicited somatosensory evoked potentials and spinal cord posterior column abnormalities in MRI were observed in sensory ataxic, painful and autonomic neuropathy. Sural nerve biopsy specimens (n = 55) revealed variable degrees of axon loss. Predominantly large fibre loss was observed in sensory ataxic neuropathy, whereas predominantly small fibre loss occurred in painful sensory neuropathy. Angiitis and perivascular cell invasion were seen most frequently in multiple mononeuropathy, followed by sensory ataxic neuropathy. The autopsy findings of one patient with sensory ataxic neuropathy showed severe large sensory neuron loss paralleling to dorsal root and posterior column involvement of the spinal cord, and severe sympathetic neuron loss. Degrees of neuron loss in the dorsal and sympathetic ganglion corresponded to segmental distribution of sensory and sweating impairment. Multifocal T-cell invasion was seen in the dorsal root and sympathetic ganglion, perineurial space and vessel walls in the nerve trunks. Differential therapeutic responses for corticosteroids and IVIg were seen among the neuropathic forms. These clinicopathological observations suggest that sensory ataxic, painful and perhaps trigeminal neuropathy are related to ganglioneuronopathic process, whereas multiple mononeuropathy and multiple cranial neuropathy would be more closely associated with vasculitic process.

Effect of lung-protective ventilation on severe Pseudomonas aeruginosa pneumonia and sepsis in rats.

Pneumonia caused by Pseudomonas aeruginosa carries a high rate of morbidity and mortality. A lung-protective strategy using low tidal volume (V(T)) ventilation for acute lung injury improves patient outcomes. The goal of this study was to determine whether low V(T) ventilation has similar utility in severe P. aeruginosa infection. A cytotoxic P. aeruginosa strain, PA103, was instilled into the left lung of rats anesthetized with pentobarbital. The lung-protective effect of low V(T) (6 ml/kg) with or without high positive end-expiratory pressure (PEEP, 10 or 3 cmH(2)O) was then compared with high V(T) with low PEEP ventilation (V(T) 12 ml/kg, PEEP 3 cmH(2)O). Severe lung injury and septic shock was induced. Although ventilatory mode had little effect on the involved lung or septic physiology, injury to noninvolved regions was attenuated by low V(T) ventilation as indicated by the wet-to-dry weight ratio (W/D; 6.13 +/- 0.78 vs. 3.78 +/- 0.26, respectively) and confirmed by histopathological examinations. High PEEP did not yield a significant protective effect (W/D, 4.03 +/- 0.32) but, rather, caused overdistension of noninvolved lungs. Bronchoalveolar lavage revealed higher concentrations of TNF-alpha in the fluid of noninvolved lung undergoing high V(T) ventilation compared with those animals receiving low V(T). We conclude that low V(T) ventilation is protective in noninvolved regions and that the application of high PEEP attenuated the beneficial effects of low V(T) ventilation, at least short term. Furthermore, low V(T) ventilation cannot protect the involved lung, and high PEEP did not significantly alter lung injury over a short time course.