Urinary leakage of tubular enzymes after shock wave lithotripsy.

OBJECTIVES: Urinary loss of tubular marker enzymes following shock wave lithotripsy (SWL) suggests corresponding morphological changes in the kidney. To date, the morphological correlate of enzymuria and its dependence on the energy applied remains unclear. METHODS: In an animal study, the acute morphological changes occurring in the tubulus cells as the basis of enzymuria were investigated. It was evaluated whether SWL-induced enzymuria correlates with the extent of renal damage. RESULTS: Acute morphological changes in the tubulus cells were demonstrated beneath isolated tubulus necrosis. The mechanically induced lesions of the cell organelles included fragmentation of the lysosomes and severe alterations of the cell membrane. The tubulus damage can be quantified. With the help of histochemical N-acetyl-beta-D-glucosaminidase (NAG) staining and electron microscopic observations, a significant correlation was found between the shock wave parameters number of impulses and intensity and the tubular damage. The intensity of NAG enzymuria reflected the severity of the tubular damage. CONCLUSIONS: In this animal model, NAG proved to be a suitable marker enzyme for estimation of the degree of SWL-induced tubular damage.

Ultrastructural studies of acute rejection following single lung transplantation in the rat--histological and immunohistological findings.

Nowadays the acute and especially chronic lung rejection are the major problems after lung transplantation (L-Tx) with relevant influence on longterm survival. We performed lung transplantation in rats to study a possible role of ultrastructural lesions in the graft during the acute rejection process, concerning their reversibility/irreversibility and influence of the chronic rejection. Based on histologic and immunohistologic studies after L-Tx in MHC-different and strong reactive rat strain combination AVN-LEW and filial generation (AVN-LEW)F1-LEW (n = 57 and n = 32) electronmicroscopic studies (TEM, SEM) were performed in the combination AVN-LW (n = 20) on postoperative day 0, 1, 2 and 5, all without immunsuppressive therapy. Syngenic grafts (LEW-LEW; n = 12) served as controls. Histologically the allografts were classed according to the proven acute rejection phases latent, vascular, alveolar and destructive. The immunhistological and electronmicroscopic results correlated with these rejection phases. There was no difference between the rat strain combinations. All allografts developed acute rejection on postoperative day 2 and were destroyed on postoperative day 5/6. Initially T-helper-cells, later cytotoxic-T-cells and macrophages played the predominent role in the acute rejection process. In the ultrastructural specimens alterations of the blood vessels, pneumocytes type-II, and surfactant gave more information. Initially flattening of endothelial cells and circumscribed lesions of graft vessels occur, increasing in the allografts up to extensive vascular wall destructions, accompanied by total thrombotic occlusion. Disturbances of surfactant production observed in the grafts of all strain combinations are not homogenous.(ABSTRACT TRUNCATED AT 250 WORDS)