Mycotic Lesions in Surgical Pathology.

Kalyani, S (2010) Mycotic Lesions in Surgical Pathology. Masters thesis, Coimbatore Medical College, Coimbatore.


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The Fungal Diseases Are Grouped Arbitrarily Into Four Broad Categories Based On The Predominant Location Of Infection Within The Body As Superficial, Cutaneous, Subcutaneous And Systemic Infection. Superficial Mycoses Are Those In Which The Fungus Is Usually Confined To The Keratinized Layer Of The Skin And Its Appendages. The Cutaneous And Subcutaneous Mycoses Are A Polymorphic Group Of Diseases Caused By A Variety Of Fungi. Systemic Mycoses Usually Have A Pulmonary Inception From Which They Disseminate To Other Organs. Most Fungal Infections Occur Because A Person Is Exposed To A Source Of Fungi Such As Spores On Surfaces Or In The Air, Soil Or Bird Dropings. Usually There Is A Break Or Deficiency In The Bodys Immune System Defences And The Person Provides The “Right Environment” For The Fungi To Grow. Any One Can Have A Fungal Infection But Certain Populations Are At Increased Risk Of Fungal Infections And Recurrence Of The Infection. These Include HIV–AIDS Spectrum, Malignancy, Multidrug Resistant Tuberculosis, Diabetes Mellitus, Organ Transplant Recipients, Those Who Are On Chemotherapy Or Immunosuppressants, Prolonged Intake Of Steroids For Chronic Disorders Like Bronchial Asthma, Rheumatoid Arthritis And Inborn Immunological Deficiencies. Neutropenic Patients Are Prone To Develop Invasive Mycosis. Persons Who Have Undergone Abdominal Or Cardiac Surgery And Those Who Received Repeated Intravenous Injections Are At Risk Of Mycoses. In The Macroscopic Evaluation Of Tissue Specimens, Mycotic Infections Are Frequently Mistaken For Neoplasms Or Other Diseases And A Mycosis Often May Not Be Considered Until The Histopathological Examination Is Complete2. There Are Four Basic Approaches To The Diagnonsis Of Mycotic Diseases: (1) Clinical (2) Mycologic (3) Immunologic (4) Pathologic. Diseases Caused By Fungi May Be Difficult To Distinguish Both Clinically And Pathologically From Those Caused By Other Microbial Agents. Because Serological Test Have Certain Limitations And Have Not Been Developed For Some Fungal Diseases, A Definitive Diagnosis Of Mycotic Disease Often Rests On Direct Microscopic Demonstration Of A Fungus In Tissues And Exudates, Or On Isolating And Identifying It In Culture. Histopathology Should Not Be A Substitute For Mycologic Culture ; Rather The Two Should Complement Each Other Whenever Possible.Histopathologic Evaluation Provides Indisputable Evidence Of Tissue Invasion And Therefore Can Confirm The Pathogenic Significance Of A Cultural Isolate That Belongs To The Body Flora Or That Is Usually Encountered As An Environmental Contaminant In Culture. Histopathology Can Also Confirm The Presence Of Coexisting Infections By Other Fungi, Bacteria, Viruses And Protozoans Thus Guiding The Clinician In The Selecting The Most Appropriate Therapy And Management For The Patient. Although Some Fungi And Related Organisms Can Be Detected In Hematoxylin And Eosin Stained Tissue Sections, Special Histochemical Stains Are Usually Necessary To Demonstrate Their Morphology In Detail. Fungi Can Be Adequately Detected In Cytologic Specimens Obtained By Fine Needle Aspiration Biopsy, Brushing, Washing Or Scraping. A Drawback Of Cytologic Specimens However May Be The Inability To Distinguish Invasive Fungal Infections From Fungal Colonization1. The Three Common Fungal Stains Used Are Gomori Methenamine Silver (GMS)5,36, The Gridley Fungus (GF), And The Periodic Acid – Schiff (PAS) Procedures. GMS Procedure Is Considered To Be The Best Of The Special Fungal Stains For Screening A Tissue Section Because It Provides Better Contrast And Stains Fungal Cells That Are Refractory To The GF And PAS Procedures.

Item Type: Thesis (Masters)
Uncontrolled Keywords: Mycotic Lesions ; Surgical Pathology.
Subjects: MEDICAL > Pathology
Depositing User: Subramani R
Date Deposited: 29 Jun 2017 01:56
Last Modified: 29 Jun 2017 01:56

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