Bleomycin toxicity affects which type of cells: (REPEAT)
Bleomycin :This is a mixture of closely related glycopeptide antibiotics having potent antitumour activity. It chelates copper or iron, produces superoxide ions and intercalates between DNA strands-causes chain scission and inhibits repair . It is highly effective in testicular tumour and squamous cell carcinoma of skin, oral cavity, head and neck, genitourinary tract and esophagus; also useful in Hodgkin&;s lymphoma. Mucocutaneous toxicity and pulmonary fibrosis, but little myelosuppression are the special features. Bleomycin-induced lung injury typically occurs insidiously during the first 6 months after staing treatment, but the potential for high-inspired fractions of oxygen to provoke pulmonary toxicity remains a life-long risk. The main abnormalities in bleomycin-induced pulmonary toxicity occur in endothelial and epithelial cells. Destruction and desquamation of type I pneumocytes occur, as does the proliferation of type II pneumocytes. Mononuclear cell infiltration, fibroblast proliferation, and fibrosis are common findings. Bronchoalveolar lavage studies in patients with bleomycin-induced pneumonitis have shown the presence of polymorphonuclear alveolitis. REFERENCE: www.medscape.com, essentials of medical pharmacology(k.d.tripathi,sixth edition,page no:826,827)
Type-I pneumocytes
Type-II pneumocytes
Endothelial cells
Pulmonary alveolar macrophages
Chemotherapy