Primary tuberculosis LECTURE doc. Kravchenko N.S.
Tuberculosis which develops in primary infected people is called primary tuberculosis. It is diagnosed often in children and teenagers. More rarely in young people. Topical sings of primary tuberculosis are: a) The intensity tuberculin test reaction; b) lesion of lymphatic system (especially lymphatic nodes); c) tendency to lymphogenous and hematogenous dissemination; d) state of hypersensibilization of organism to pathogenic agent; e) possibility of spontaneous recovery. Tuberculin skin conversion is the appearance of first positive tuberculin reaction after a negative one within a year or its increase in persons vaccinated. The period from the moment of the intensity of tuberculin reaction during one year without signs of intoxication is called the period of early tuberculous infection.
Primary tuberculosis usually displays in three main forms: - tuberculous intoxication in children and teenagers (tuberculosis without established localization); - primary tuberculous complex; - tuberculosis of intrathoracic lymphatic nodes.
PATHOGENESIS IN CHILDREN Primary tuberculosis is always result of exogenous infection. The infection penetrates into organism by: - aerogenic (the most often way of penetration) - alimentary; - contact way. 1. The primary complex of tuberculosis consists of local disease at the portal of entry and the regional lymph nodes that drain the area of the primary focus. In more than 95% of cases the portal of entry is the lung. M. tuberculosis within particles larger than 10 (xm usually are caught by the mucociliary mechanisms of the bronchial tree and are expelled. Small particles are inhaled beyond these clearance mechanisms. However, primary infection may occur anywhere in the body. 2. Ingestion of milk infected with bovine tuberculosis can lead to a gastrointestinal primary lesion. 3. Infection of the skin or mucous membrane can occur through an abrasion, cut, or insect bite.
Tuberculous intoxication Tuberculous intoxication in children and teenagers is a clinical form of primary tuberculosis, which is characterized by complex of symptoms of functional derangement without local manifestation of disease. Morfological substrat of tuberculous intoxication are minimal specific (tuberculous granuloma with areas of microcaseose) and paraspecific changes, usually in lymphatic system.
ERYTHEMA NO DOSUM
Differential diagnosis. It is necessery to exclude diseases accompanied by intoxication: chronical sourses of infection of oral cavity and epipharynx, chronical tonsillitis, pielonephritis, rheumatism, hepatocholecystitis, helminthic invasions. Main diagnostic criterions of tuberculous intoxication are: - tuberculin skin conversion - symptoms of intoxication - absence of roentgenological changes - excluding of intoxication with different ethiology Treatment. Isoniazidum 10mg/kg of weight + rifampicinum10 mg/kg + ethambutol 20mg/kg for 4-6 months, vitamins B1, B6, C.
Primary tuberculous complex Primary tuberculous complex Primary tuberculous complex is characterized by development of specific general changes in lungs (primary effect), lesion of intrathoracic lymphatic nodes and lymphangitis. Patological anatomy: zone of tuberculous granulations and caseous necrosis is forming in lungs. Zone of perifocal toxic edema and serofibrinous inflammation is forming around zone of specific inflammation. These changes form primary affect. Infection extence in lymphatic vessels from primary affect to the root of lungs (lymphangitis) and injury of root lymphatic nodes is taking place (lymphadenitis). fig. 1
fig.1 P rimary tuberculous complex
Clinical manifestations. Asymptomatic course of disease can be present under little specific changes in lungs. Complaints: subfebrile temperature, decrease of body weight, bad appetite, quick tiredness. Coughing happens seldom. Inspection: paleness, decrease of skin turgor, paraspecific changes, micropolyadenitis. These changes can be absent. Percussion: dullness over lung component with a big size. Weakend breathing with streached exhale. Hemogram: Leucocytosis T/l, insignificant shift to the left, lymphopenia, monocytosis, ESR mm/h. Tuberculin test - intensivity of tuberculin reaction, hyperergic reaction. MBT are rarely to be found. X-ray diagnostics: Phases: 1) infiltrative or pneumonic; 2) resorbtion (suction,bipolarities); 3) scarring 4) calcification.
fig. 2 Primary tuberculous complex, infiltration phase
Primary tuberculous complex, infiltration phase
Phase 1: infiltrative or pneumonic
Phase 2: resorbtion (suction,bipolarities)
Phase 3: scarring
Phase 4: calcification
infiltrative or pneumonic resorbtion (suction,bipolarities) calcification PHASES OF PRIMARY TUBERCULOUS COMPLEX
Complications are connected with lung component: If caseation is intense, the center of the lesion may liquefy, empty into the associated bronchus, and leave a residual primary tuberculous cavity. Complications connected with regional lymphadenitis: - hematogenic dissemination - lymphogenic dissemination - pleuritis - extending of specific process from lymphatic node It’s results: a) formation of fistula b) dispersion of caseous masses, bronchogenic dessemination, bronchi tuberculosis c) disorder of bronchial permeability, atelectasis
Bronchogenic dissemination
Acute Disseminated Primary TB (often in children aged under 5 years) –Miliary with or without meningitis – Classified as PTB, Category I
fig. 3 Primary tuberculous complex, complication of atelectasis
Tuberculosis of intrathoracic lymphatic nodes Tuberculosis of intrathoracic lymphatic nodes is specific injury of lymphatic nodes of lungs’ root and mediastinum. Pathomorphological forms: a) hyperplastic b) caseous form The clinic of uncomplicated tuberculosis of intrathoracic lymphatic nodes is similar to that of primary tuberculous complex. Clinical-radiological forms of tuberculosis of intrathoracic nodes: 1) Small form – deformation and strengthening of pulmonary picture near lung root, decreasing of root structure. 2) Infiltrative – root shadow is widened with not clear contour (ouyline). 3) Tumorshaped – widening of mediastinum or lung root with polycicle clear contour
fig. 5 Tuberculosis of intrathoracic lymphatic nodes
Primary TB Disease: –Often unilateral lymphadenopathy, hilar, mediastinal, paratracheal or subcarinal without obvious parenchymal involvement – Most frequent presentation in children (70-80%) – Classify as EPTB and treat as Category III
fig. 4 Roentgenogram of the thoracic cage organs. Tuberculosis of intrathoracic lymphatic nodes
INFILTRATIVE FORM OF TUBERcULOSIS OF INTRATHORACIC LyMPHATIC NODES
TUMOURSIMILAR FORM OF TUBERcULOSIS OF INTRATHORACIC LyMPHATIC NODES
fig. 6 Roentgenogram of the thoracic cage organs. Lymphosarcoma, complication of pleurisy
fig. 7 Roentgenogram of the thoracic cage organs. Lymphogranulomatosis.
fig. 8 Roentgenogram of the thoracic cage organs. Sarcoidosis of intrathoracic lymphatic nodes.