GANGRENE

1. GANGRENE DEFINITION - IS A FORM OF NECROSIS OF TISSUE WITH SUPERADDED PUTREFACTION GANGRENE IS CAUSED BY ISCHAEMIA OR INFECTION

2. GANGRENE NECROSIS IS USUALLY COAGULATIVE DUE TO ISCHAEMIA WITH SUPERADDED PTREFACTION BY PUTREFYING BACTERIA • EXAMPLE –GANGRENE OF THE BOWEL,GANGRENE OF THE LIMBS

3. CAUSES OF GANGRENE ANY CONDITION THAT AFFECTS BLOOD FLOW INCREASES THE RISK OF GANGRENE, INCLUDING:  1.DIABETES 2. ATHEROSCLEROSIS 3. PERIPHERAL ARTERIAL DISEASE 4.TRAUMA OR INJURY 5. RAYNAUD'S PHENOMENON (A CONDITION IN WHICH THE BLOOD VESSELS THAT SUPPLY THE SKIN BECOME INTERMITTENTLY NARROWED –CAUSE IS NOT KNOWN)

4. RAYNAUD'S PHENOMENON PRIMARY RAYNAUD'S IS WITHOUT AN UNDERLYING DISEASE OR ASSOCIATED MEDICAL PROBLEM THAT COULD PROVOKE VASOSPASM. ATTACKS ARE TRIGGERED BY EXPOSURE TO COLD AND/OR STRESS, SYMMETRIC BILATERAL INVOLVEMENT, NO DETECTABLE UNDERLYING CAUSE,

5. RAYNAUD'S PHENOMENON NORMAL CAPILLAROSCOPY FINDINGS, NORMAL LABORATORY FINDINGS FOR INFLAMMATION, AND AN ABSENCE OF ANTINUCLEAR FACTORS. SYMPTOMS OF RAYNAUD'S PHENOMENON DEPEND ON THE SEVERITY, FREQUENCY, AND DURATION OF THE BLOOD-VESSEL SPASM .IT IS ACCOMPANIED BY PARESTHESIAS AND PAIN

6. RAYNAUD'S PHENOMENON INITIALLY, THE DIGIT(S) INVOLVED TURN WHITE BECAUSE OF THE DIMINISHED BLOOD SUPPLY. THE DIGIT(S) THEN TURN BLUE BECAUSE OF PROLONGED LACK OF OXYGEN. FINALLY, THE BLOOD VESSELS REOPEN, CAUSING A LOCAL "FLUSHING" PHENOMENON, WHICH TURNS THE DIGIT(S) RED.

7. RAYNAUD'S PHENOMENON THIS THREE-PHASE COLOR SEQUENCE (WHITE TO BLUE TO RED), MOST OFTEN UPON EXPOSURE TO COLD TEMPERATURE, IS CHARACTERISTIC OF RAYNAUD'S PHENOMENON

8. RAYNAUD'S PHENOMENON

9. GANGRENE DUE TO RAYNAUD'S PHENOMENON

10. RAYNAUD PHENOMENON CHRONIC, RECURRENT CASES OF RAYNAUD PHENOMENON CAN RESULT IN ATROPHY OF THE SKIN, SUBCUTANEOUS TISSUES, AND MUSCLE. IN RARE CASES IT CAN CAUSE ULCERATION AND ISCHEMIC GANGRENE

11. GANGRENE SECONDARY RAYNAUD'S WHICH IS A SYNDROME CAUSED BY A KNOWN PRIMARY DISEASE, MOST COMMONLY CONNECTIVE TISSUE DISORDERS SUCH AS SYSTEMIC LUPUS ERYTHEMATOSUS, SCLERODERMA

12. GANGRENOUS OR NECROTISING INFLAMMATION IN THIS CASE INFLAMMATION IS PRIMARY PROVOKED BY A VIRULENT BACTERIA RESULTING IN MASSIVE TISSUE NECROSIS. EXAMPLE – GANGRENOUS APPENDICITIS, GANGRENOUS STOMATITIS(NOMA OR CANCRUM ORIS)

13. GANGRENOUS OR NECROTISING INFLAMMATION THE RESULT OF NECROTISING OR GANGRENOUS INFLAMMATION AND GANGRENE IS THE SAME BUT THE MECHANISM IS DIFFERENT

14. 3 MAIN FORMS OF GANGRENE THERE ARE DIFFERENT TYPES OF GANGRENE WITH DIFFERENT SYMPTOMS 1.DRY GANGRENE 2.WET GANGRENE 3.GAS GANGRENE

15. DRY GANGRENE BEGINS IN THE DISTAL PART OF THE LIMB DUE TO ISCHAEMIA AND OFTEN OCCURS IN THE TOES AND FEET OF ELDERLY PATIENTS DUE TO GRADUAL LOSS OF BLOOD SUPPLY AS IN ATHEROSCLEROSES

16. DRY GANGRENE OTHER CAUSES OF DRY GANGRENE FOOT ARE THROMBOANGITIS OBLITERANS ,ALSO KNOWN AS BUERGER’S DISEASE (THROMBOANGIITIS OBLITERANS - BUERGER'S DISEASE IS A RECURRING PROGRESSIVE INFLAMMATION AND THROMBOSIS OF MEDIUM SIZED ARTERIES AND VEINS OF HANDS AND FEET) ,

17. DRY GANGRENE RAYNAUD’S DISEASE,TRAUMA , ERGOT POISONING - INGESTION OF THE ALKALOIDS PRODUCED BY THE CLAVICEPS PURPUREA FUNGUS THAT AFFECTS RYE GRAIN -THE DRY GANGRENE IS A RESULT OF VASOCONSTRICTION INDUCED BY THE ERGOTAMINE-ERGOCRISTINE ALKALOIDS OF THE FUNGUS.

18. DRY GANGRENE STARTS IN ONE OF THE TOES WHICH IS FARTHEST FROM THE BLOOD SUPPLY,CONTAINING VERY LITTLE BLOOD THAT EVEN INVADING BACTERIA FIND DIFFICULT TO GROW IN THE NECROSED TISSUE

19. DRY GANGRENE THE GANGRENE SPREADS SLOWLY UPWARDS UNTIL IT REACHES A POINT WHERE THE BLOOD SUPPLY IS ADEQUATE TO KEEP THE TISSUE VIABLE THUS A LINE OF SEPARATION IS FORMED

20. DRY GANGRENE -MORPHOLOGY GROSS THE AFFECTED PART IS DRY,SHRUNKEN AND DARK BLACK(DUE TO PRODUCTION OF BLACK IRON SULFIDE) RESEMBLES A FOOT OF MUMMY

21. DRY GANGRENE -MORPHOLOGY THE LINE OF SEPERATION BRINGS ABOUT COMPLETE SEPERATION WITH EVENTUAL FALLING OF THE GANGRENOUS TISSUE

22. DRY GANGRENE -GROSS

23. DRY GANGRENE -MORPHOLOGY MICROSCOPY – NECROSIS ( COAGULATION NECROSIS) GRANULATION TISSUE AT THE LINE OF SEPERATION

24. DRY GANGRENE - MICROSCOPY

25. GRANULATION TISSUE

26. WET GANGRENE OCCURS IN NATURALLY MOIST TISSUES AND ORGANS SUCH AS MOUTH, BOWEL,LUNG,CERVIX, VULVA etc EXAMLE – DIABETIC GANGRENE DUE TO HIGH SUGAR CONTENT IN THE NECROSED TISSUE WHICH FAVOURS GROWTH OF BACTERIA

27. WET GANGRENE BED SORES IN BED RIDDEN PATIENT DUE TO PRESSURE ON SITES LIKE SACRUM,BUTTOCKS AND HEELS IS ANOTHER EXAMPLE OF WET GANGRENE

28. WET GANGRENE DEVELOPS RAPIDLY DUE TO BLOCKAGE OF VENOUS, AND LESS COMMONLY,ARTERIAL BLOOD FLOW FROM THROMBOSIS AND EMBOLISM

29. WET GANGRENE THE AFFECTED PART IS STUFFED WITH BLOOD WHICH FAVOURS RAPID GROWTH OF PUTREFACTIVE BACTERIA

30. WET GANGRENE

31. WET GANGRENE

32. WET GANGRENE- MORPHOLOGY TOXIC PRODUCTS FORMED BY BACTERIA ARE ABSORBED CAUSING SYSTEMIC MANIFESTATION OF SEPTICAEMIA, FINALLY DEATH RAPIDLY SPREADING WET GANGRENE LACKS CLEAR CUT LINE OF DEMARCATION

33. WET GANGRENE- MORPHOLOGY GROSS – AFFECTED PART IS SOFT, SWOLLEN,PUTRID ,ROTTEN AND DARK EXAMPLE –GANGRENE OF THE BOWEL,COMMONLY DUE STRANGULATED HERNIA, VOLVULOUS OR INTUSCEPTION

34. WET GANGRENE- MORPHOLOGY THE PART IS STAINED DARK MICROSCOPY – COAGULATIVE NECROSIS WITH STUFFING OF AFFECTED PART WITH BLOOD. ULCERATION OF THE MUCOSA WITH SEVERE ACUTE INFLAMMATION LINE OF DEMARCATION IS NOT CLEAR CUT

35. GAS GANGRENE IS A SPECIAL FORM OF WET GANGRENE CAUSED BY GAS FORMING CLOSTRIDIA(GRAM- POSITIVE ANAEROBIC BACTERIA) WHICH GAIN ENTRY INTO THE TISSUES THROUGH OPEN CONTAMINATED WOUNDS

36. GAS GANGRENE CLOSTRIDIA PRODUCE VARIOUS TOXINS WHICH PRODUCE NECROSIS,EDEMA LOCALLY THE TOXINS GET ABSORBED AND PRODUCING SEVERE SYSTEMIC MANIFESTATIONS

37. GAS GANGRENE - MORPHOLOGY GROSS - AFFECTED AREA SWOLLEN, EDEMATOUS,PAINFUL AND CREPITANT DUE TO ACCUMULATION OF GAS BUBBLES WITHIN THE TISSUES THE AFFECTED TISSUE BECOME DARK BLACK AND FOUL SMELLING

38. GAS GANGRENE - MORPHOLOGY -GROSS

39. GAS GANGRENE - MORPHOLOGY MICROSCOPY – COAGULATIVE NECROSIS WITH LIQUIFACTION AND LARGE NO OF GRAM +VE BACILLI ARE SEEN AT THE PERIPHERAL ZONE CONGESTION , EDEMA ,LEUKOCYTIC INFILTRATE WITH CAPILLARY AND VENOUS THROMBI

40. DIFFERENCES BETWEEN DRY AND WET GANGRENE