Central nervous system involvement in patients with monoclonal gammopathy and polyneuropathy.

BACKGROUND AND PURPOSE: To evaluate clinical presentation of patients with the clinical triad of monoclonal gammopathy, polyneuropathy and signs of CNS involvement. METHODS: Nineteen patients with monoclonal protein (M-protein, 9 IgM, 10 IgG) were studied. Clinical examination, MRI, cerebrospinal fluid analysis and immune reactivity against myelin-associated glycoprotein and gangliosides in serum were obtained. By immunohistochemistry, different binding patterns of M-proteins to human CNS tissue were investigated. RESULTS: Nine out of 19 patients (four IgM, five IgG) showed one or more clinical signs of CNS involvement. Clinical features associated with signs of CNS pathology were disease duration and greater concentration of IgM paraprotein. The IgM M-protein of two patients strongly stained the cortex/cerebellar neurons in human brain sections. CONCLUSION: Our results complement previous reports that some patients with monoclonal gammopathy and polyneuropathy can develop solitary or disseminated signs of CNS involvement. It indicates that pathological effects of M-proteins are not necessarily restricted to the peripheral nervous system. The specificity and affinity of circulating M-protein to antigens in the CNS might be critical for the development of different clinical phenotypes.

[Seasonal variations in the incidence of the conception of multiple pregnancies in two centuries (author's transl)]. / Die jahreszeitlichen Schwankungen der Häufigkeit von Mehrlingskonzeptionen im Wandel zweier Jahrhunderte.

Seasonal variations in the incidence of the conception of multiple pregnancies are compared in the same population area in two centuries. 12,617 singleton and 101 twin pregnancies from 1803 to 1852 are compared to 63,967 singleton, 473 twin and 5 triplet pregnancies from 1965 to 1970. In both groups the percentage decrease of multiple conceptions during the first three months of the year was higher than the percentage decrease of singleton conceptions. In both groups the percentage increase of multiple conceptions during the summer months was higher than the percentage increase of singleton conceptions. The question of the influence of light on the hypothalamic-pituitary centres as a cause of the variations in multiple conceptions is discussed. The incidence of multiple conceptions has decreased since the beginning of the 19th century independant of the progress in obstetrics and perinatology. The decreased rate of multiparas and especially older multiparas is suggested as the likely cause for this decrease.