第13章 分枝杆菌属

(tubercle bacilli): 为结核病的病原体。
"Tuberculosis" comes from the Latin word, tuberculum, meaning "protuberance, projection or growth," and refers to the tumorlike nodules that victims often display. In fact, until TB's bacterial agent was discovered in 1882, many physicians thought TB's characteristic nodules and wasting identified it as a form of cancer.
Estimated TB Incidence, Prevalence and Mortality, 2005
Incidence All forms Smear-positiveb Prevalence TB Mortality
WHO region
number (thousan ds)
(% of global total) 2 529 (29) 352 (4)
343 39
1 088 157
147 18
3 773 448
511 50
544 49
74 5.5
565 (6) 445 (5) 2 993 (34) 1 927 (22) 8 811 (100)
104 50 181 110 136
253 199 1 339 866 3 902
47 23 81 49 60
Fig.1 Initial chest radiograph of a pregnant woman
Additional infiltrates could be seen in the entire left lung and in the right parahilar mid-lung field. Several concentrated sputum samples revealed numerous acidfast bacilli. Daily antituberculous therapy was initiated with rifampin, 600 mg, isoniazid, 300 mg, and ethambutol, 700 mg (with a target of 15 mg/kg). One smear-positive specimen was immediately processed for susceptibility testing after communicating with the mycobacteriology laboratory. After 3 weeks of treatment, the patient continued to have a temperature of up to 39.4°C and experienced a weight loss of about 5 kg. A repeat chest radiograph revealed a worsening of the left lung infiltrate and a persistence of the rightsided infiltrate.
• 生化反应
– 不发酵糖类
– 触酶试验阳性
– 热触酶试验阴性
• 抵抗力强
– 抗干燥，抗酸碱，抗化学消毒剂； – 对湿热和紫外线敏感； – 对抗结核药（异烟肼、利福平、环丝氨酸 、乙胺丁醇等）敏 感，但易产生耐药性。
• 变异性：结核杆菌多种性状可发生变异
– 形态变异：在异烟肼、溶菌酶等作用下形成L型（多形性）； – 菌落变异：R-S型变异，性状典型→不典型，毒力减弱； – 毒力变异：卡介苗（Bacilli Calmette-Guerin, BCG）： 1908年两位科学家将有毒的牛型分枝杆菌接种在含甘油、 胆汁、马铃薯的培养基中，经13年230代传代获得的减毒菌 株，即卡介苗沿用至今；
percent of avoidable deaths in the developing world. The Global Burden of Disease study places TB among the seven leading causes of lost Disability-Adjusted Life Years (DALYs) well into the
per 100 000 pop
number (thousan ds)
per 100 000 pop
number (thousan ds)
per 100 000 pop
number (thousan ds)
per 100 000 pop
Africa The Americas Eastern Mediterran ean Europe South-East Asia Western Pacific Global
• Mycobacterium tuberculosis complex (MTBC) members are causative agents of human and animal tuberculosis. • Species in this complex include:
– – – – – – – – M. tuberculosis, the major cause of human tuberculosis M. bovis M. bovis BCG M. africanum M. canetti M. caprae M. microti M. pinnipedii
Robert Koch (1843-1910)
Tuberculosis incidence rate, 2004.
Multi-drug resistant tuberculosis, 2004
distribution of proportion of MDR-TB among new TB cases, 1994-2009 / WHO
第十三章 分枝杆菌属
(Mycobacterium)
第一节 结核分枝杆菌 第二节 麻风分枝杆菌 第三节 其他分支杆菌
• 分枝杆菌属(Mycobacterium): 是一类细长略弯曲的杆菌，因繁殖时有分枝 生长趋势而得名。
Scientific classification Kingdom: Phylum: Order: Bacteria Actinobacteria Actinomycetales
• • •
A 22-year-old gravid African-American woman was evaluated at 23 weeks’ gestation during her second pregnancy because of a positive tuberculin skin test result with 18 mm of induration. The patient reported a history of dry cough and fever for 2 months, and weight loss and night sweats for 1 month. She denied hemoptysis. The findings of her physical examination were unremarkable except for a body weight of 48 kg (body mass index, 18.3 kg/m2). On examination, her temperature was 42°C. Breath sounds were normal, and there were no crackles, rales, or rhonchi. The patient was admitted to the hospital. The chest radiograph revealed a left upper lung cavity (Fig 1 ).
Suborder:
Family: Genus:
Corynebacterineae
Mycobacteriaceae Mycobacterium
The classification-based upon cladistics
1 Slowly growing 1.1 Mycobacterium tuberculosis complex (MTBC) members are causative agents of human and animal tuberculosis. 1.2 Mycobacterium avium complex (MAC), is a group of species which, in a disseminated infection but not lung infection, used to be a significant cause of death in AIDS patients. 1.3 Mycobacterium gordonae clade 1.4 Mycobacterium kansasii clade 1.5 Mycobacterium nonchromogenicum/terrae clade 1.6 Mycolactone-producing mycobacteria M. ulcerans, which causes the "Buruli", or "Bairnsdale, ulcer" 1.7 Mycobacterium simiae clade 1.8 Ungrouped M. leprae, which causes leprosy 2 Intermediate growth rate 3 Rapidly growing 4 Ungrouped