9. PATHOGENESIS
Brucella organism Phagocytosis by macrophages Survive inside the macrophages
Prevents fusion of lysosome with phagosomes
Bacteria not exposed to lysososmal enzymes
Bacteria grows inside phagosomes of macrophages Hence antibodies are in effective against bacteria
Macrophages rupture, release the bacteria
11. CLINICAL FEATURES
• OFTEN FITS ONE OF THE THREE PATTERN:
1) FEBRILE ILLNESS RESEMBLING TYPHOID ,LESS SEVERE
2) FEVER &ACUTEMONOARTHRITIS
(HIP/KNEE),YOUNGCHILD
3) LONGLASTINGFEVER,LBA,HIPPAIN,OLDERMAN
• TRAVELTOANENDEMIC AREA
• OCCUPATION
• CONSUMPTION OF UNPASTEURIZEDMILK
12. • PHYSICALMANIFESTATIONS MAY BE ABSENT.
• IF PRESENT, FOCALFEATURES:
• MUSCULOSKELETALPAIN
• OSTEOMYELITIS
• SEPTICARTHRITIS
• MINIMAL LYMPHADENOPATHY
• HEPATOSPLENOMEGALYOCCASIONALLY
13. • ENDOCARDITIS —1PERCENT.
• MOST OFTEN AFFECTING AORTIC VALVE(NATURAL/PROSTHETIC)
• NEURALGIC INVOLVEMENT-LTMPHOCYTIC
MENINGOENCEPHALITIS,INTRACEREBRAL ABSCESS
• HEPATIC ABSCESS—1PERCENT
• OTHER LESSCOMMON COMPLICATIONS INCLUDE PNEUMONITIS,
PLEURAL EFFUSION, EMPYEMA,,OR ABSCESS INVOLVING THE
SPLEEN,THYROID, OR EPIDURAL SPACE,UVEITIS.
15. LAB DIAGNOSIS
• TOTALCOUNT S-NORMAL/REDUCED
• THROMBOCYTOPENIA
• ESR/CRP-NORMAL/INCREASED
• CSF/BODYFLUID ANALYSIS-LYMPHOCYTOSIS, LOW GLUCOSELEVELS,
ELEVATED ADA
• BIOPSIED SAMPLES OF LYMPH NODE, LIVER- NON CASEATING
GRANULOMAWITHOUTACID FASTBACILLI.
16. BLOOD CULTURES IN
TRYPTICASE SOYA BROTH
(CASTANEDA’S METHOD):
DEFINITIVE METHOD OF DIAGNOSIS
BIPHASIC MEDIUM.
SAMPLE INOCULATED BOTTLE HAS TO
BE TILTED TO FLOW THE BROTH OVER
SOLID MEDIUM AND KEEP IT UPRIGHT
POSITION AT 370C .
THE GROWTH OF BRUCELLAE IS
EXTREMELY SLOW.
BONE MARROW CULTURES ARE MORE
SENSITIVE THAN BLOOD.
17. SEROLOGY
MAINLABORATORYMETHOD OF DIAGNOSIS
SERUMAGGLUTINATION TEST- MOSTWIDELY USED
MEASURESAGGLUTINATION FOR IGG,IGM,IGA
• 2ME- BREAKSULF-HYDRILEBONDSIN IGM POLYMER - NO
AGGLUTINATION
DIAGNOSTIC 1: 160- NON ENDEMIC AREA
1: 320- ENDEMICAREA
• SAT– FALSE NEGATIVE
– PROZONE
– BLOCKINGANTIBODIES
18. ANTIGLOBULIN TEST
• ADD SERUM WITH EQUAL VOLUME OF SHEEP RBC
• INCUBATED AT 37 DEGREE CELCIUS
• WASH THRICE WITH SALINE TO REMOVE EXCESS GLOBULIN
• ADD ANTIGLOBULIN SERUM
• VISIBLE CLUMPING (POSITIVE)
20. MILK RING TEST
FREQUENTLY USED TEST.
A DROP OF COLORED BRUCELLA
ANTIGEN
(B.ABORTUS/B.MELITENSIS WITH
HEMATOXYLIN) IS ADDED TO MILK IN
A TEST TUBE, INCUBATED IN A
WATER BATH AT 700C FOR 40-50
MINUTES.
POSITIVE: BLUE RING AT THE TOP
LEAVING THE MILK UNSTAINED.
NEGATIVE: NO RING. MILK REMAINS
UNIFORMLY BLUE
21.
22. TREATMENT
• THE WORLD HEALTH ORGANIZATION RECOMMENDS THE
FOLLOWING FOR ADULTSANDCHILDRENOLDERTHAN 8YEARS:
– DOXYCYCLINE 100MG PO BID AND RIFAMPIN 600-900 MG/D PO:
BOTH DRUGS ARE TO BE GIVEN FOR 6WEEKS (MORE
CONVENIENT BUT PROBABLYINCREASESTHE RISKOF RELAPSE).
– DOXYCYCLINE 100MG PO BID FOR 6WEEKSAND STREPTOMYCIN
1G/DIM DAILY FOR 2-3 WEEKS:THIS REGIMENISBELIEVED TO
BEMOREEFFECTIVE, MAINLY IN PREVENTINGRELAPSE.
– NOTTOLERATEDOXYCYCLINEORRECEIVETETRACYCLINES
(PREGNANTANDCHILDREN)-TMP-SMX+RIFAMPIN
23. BRUCELLA
• BRUCELLA NEUROLOGIC DISEASE-CEFTRIAXONE
• BRUCELLA ENDOCARDITIS-AG+TETRACYCLINE+RIFAMPIN
+CEFTRIAXONE+FQS FOR 4-6 MONTHS
• PROSTHETIC VALVE AND JOINT INFECTION-SURGERY
24. PREVENTION AND CONTROL
EDUCATION ABOUT RISK OF TRANSMISSION
FARMER, VETERINARIAN, ABATTOIR WORKER, BUTCHER,
CONSUMER, HUNTER, PUBLIC
WEAR PROPER ATTIRE IF DEALING WITH INFECTED
ANIMALS/ TISSUES
GLOVES, MASKS, GOGGLES
AVOID CONSUMPTION OF RAW DAIRY PRODUCTS
25. IMMUNIZE IN AREAS OF HIGH PREVALENCE
• YOUNG GOATS AND SHEEP WITH REV-1
• CALVES WITH RB51
• NO HUMAN VACCINE
ERADICATE RESERVOIR
• IDENTIFY, SEGREGATE, AND OR CULL
INFECTED ANIMALS
26. REFERENCES
• HARRISON’S PRINCIPLES OF INTERNAL MEDICINE,VOLUME 1
• API TEXTBOOK OF MEDICINE ,VOLUME 1
• ANANTHANARAYANAN’S TEXTBOOK OF MICROBIOLOGY
• TEXTBOOK OF PARASITOLOGY –PANICKER
• PRINCIPLE AND PRACTICE OF INFECTIOUS DISEASES
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