brucellosis 2
TRANSCRIPT
Brucellosis
M.Karimi
Etiology• Brucella:
Abortus(Cattle),Melitensis (Sheep,Goat)Suis(Swin),Canis(Dog)
• G- Coccobacil• Aerobic, Non-spore
forming• Non motile• Blood or Choclate agar
Epidemiology
• Unpasteurized milk• Occupational events
Pathogenesis• Inoculation in skin ,Eye (Through abrasion or
conjunctiva)• Inhalation (Infected aerosol)• Ingestion (Meat, Dairy products)
Risk of infection depends1. Nutritional status2. Immune status3. Rout of inoculum4. Species of brucella
Pathogenesis• Survive& Replicate within phagocytes&Monocytes• Infected macrophages localized within reticuloendothelial
system(Granuloma formation in spleen,liver,bone marrow)
Clinical manifestationTriad: Fever, Arthralgia/Arthritis,Hepatosplenomegaly
• + History of animal or food exposure
• Acute or insidious symptoms(2-4 wk after inoculation)
• Refusal to eat• Refusal to bear weight• Lassitude• FTT• Headache• Inattention/Depression
• Abdominal pain• Headache• Diarrhea• Rash• Night sweets• Weakness• Fatigue• Cough• Vomiting• Pharyngitis
• Fever• Hepatosplenomegally• Arthralgia/Arthritis Sacroiliac,Hip,Ankle,
Diagnosis
• WBC Normal or low• + History of animal or food exposure• Recovering organisms (blood’ bone
marrow’..)• Serum agglutination test: >1/160(Antibody against Abortus ,Melitensis, Suis, but not Canis)• 2ME
• False positive SATYersinia entrocoliticaVibrio choleraeFrancislla tularensis
• False negative SAT
Prozen effect
Differential diagnosis
• Car-Scratch disease• Typhoid fever• TB• Fungal infections
Treatment> or = 9 years old
• 1-Doxycycline 200 mg/D PO 6 WK
+Streptomycin 1 g/D IM 1-2 WK
ORGentamycin 3-5 mg/kg/d IM/IV 1-2 WK
--------------------------------------------------• 2-Doxycycline 200 mg/D PO 6 WK
+Rifampin 600-900 mg/D PO 6 WK
< 9 years old
TMP-SMZ: po 45 days (TMP 10 mg/Kg/D) (SMZ 50 mg/KG/D)
+Rifampin 15-20 mg/kg/D PO 45
days
Meningitis,Osteomyelitis,Endocarditis:Doxy + Genta +/- Rifampin
calcified brucellomas in both kidneys calcified brucellomas in the spleen
Salmonellae Infections
M.Karimi
EtiologySalmonellae
(G- ‘Facultative’Bacilli)• Antigens: Flagellum(H)’ Cell wall(O)’ Envelope(Vi)• Serogroups on the basis of O antigen: A’ B’ C1’ C2’ D’ E• Serotypes: S.Typhi’ S.Paratyphi’….• Transmission: Water’ Food(beef’poultry’milk’egg’..)
Salmonella Gastroentritis (Nontyphoidal)
Epidemiology
• Age: <4 y/o (< 1y/o)• Source of infection: Poultry’eggs’ egg product ’meats’ pet reptile• Transmission: Carrier (Human)• Incubation period: 6-72 hr. (usually less than 24 hr.)
• Peak incidence: Late summer &Early fall
Pathogenesis
• Ingestion• Attached to “M” cells• Phagocytosed by macrophages• Replication• Bacteremia
Clinical manifestations
• Self limited diseases: 3-7 days• Onset: Abrupt• Nausea’ Vomiting’ Crampy abdominal pain• Loose watery stool• Malaise’ headache’ chills• Fever 38-38.9 c (70%) for 48 hour
At risk of complications• Impaired immune function(T-Cell)• HIV infection• Organ transplantation• Lymphoproliferative diseases• Hemoglobinopathies
(Sickle cell disease’..)• CGD• Malaria• Very old or very young
Complications• Dehydration’Shock• Localized infection: Pneumonia Empyema Abscesses Osteomyelitis Septic arthritis Postinfectious arthritis Pyelonephritis meningitis
Diagnosis
• Cultures (Stool’ Blood’ Urine’ Bone marrow’ CSF’…)
Treatment
• Correction of shock’ dehydration’…• Antibiotics: 1-Infants < 3 mo. 2-Child with immunodeficiency’ Malnutrition Malignancy’ Intravascular catheter or other foreign material
Treatment
• Ceftriaxone or Cefotaxime Septicemia’ Enteric fever’ Metastatic site of infection• Amoxicillin• Co-trimaxozole• Fluroqinolones• Chloramphenicol
Typhoid fever
Typhoid fever
• In US:400 Cases per year &Usually under 20 y/o
• Worldwide:16 million cases per year and 600’000 death
• Infected only human
Pathogenesis
• Invasions on upper small intestine• Monocyte phagocyte• Monocyte carry organism from blood to
other RES• Organism proliferation• Lymph node’ liver & spleen inflammation• Secondary septicemia
Salmonella Typhi
Clinical manifestation
• Infant: mild GE to severe septicemia without
diarrhea Fever’ hepatomegaly ’ jaundice’ anorexia’
lethargy’ weight loss
Clinical manifestation• Child: High fever’ malaise ’lethargy’ myalgia’ headache’ rash’
Hepatomegaly’ abdominal pain and tenderness’ diarrhea(50%)’ constipation
obtunded ’delirium’ confusion ’splenomegaly’ Macular (Rose spot) or Maculopapolar rash(30%) High T with low PR (Typically each 1 degree above 38.3° C Rise PR 10/min)
Rose spot
Complications• Intestinal perforation(0.5-3%)• Severe GI hemorrhage(1-10%)• Toxic encephalopathy• Cerebral thrombosis• Acute cerebral ataxia• Aphasia• Optic neuritis• Deafness• Transverse myelitis
• Acute cholecystitis• Pneumonia• Pyelonephritic• Endocarditis• Meningitis• Osteomyelitis• Septic arthritis
Dense chronic bone reaction due to typhoid
osteomyelitis.There is a central sequestrum
Typhoid
Diagnosis & Differential diagnosis
• Diagnosis
Cultures: Blood’ Urine’ Stool’
Bone marrow’ Lymph nodes’ Deudenal fluied’
Reticuloendothelial tissue’
• Differential diagnosis
BronchitisBronchopneumoniaGastroenteritisInfluenza
Treatment
Drugs:• Ceftriaxone• Ampicillin• Chloramphenicol• Co-Trimoxozole• Ciprofloxacin• Azithromycin
Surgery• Cholecystectomy
Prognosis
• With treatment : Mortality <1% • Without treatment : Relapse up to 10% • Chronic carrier: Excrete S.typhi for more
than 3 mo.