Chapter 16: Mycoplasma

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Chapter 16 Mycoplasma

• Family Mycoplasmaceae
• Genus Mycoplasma
• Species Mycoplasma pneumoniae
  Mycolplasma hominis Ureaplasma
  urealyticum
• General Genus Characteristics
• Small, prokaryotic organisms w/ NO PG cell walls
• Enclosed in a single, trilaminar plasma membrane
• Composed of a lipid bilayer
• Classified as plastic and pleomorphic
• Smallest of known free-living, self-replicating
  prokaryotic cells
• Frequently pass thru bacteriologic filters
• Widely distributed in nature, including normal
  flora of mouth and genitourinary tract of humans
  and other mammals
• Insensitive to antibiotics that inhibit cell
  division by preventing cell wall synthesis

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Mycoplasma

• General Genus Characteristics
• Limited biosynthetic capabilities
• Require small, organic molecules for growth
• contain sterols in cell membranes
• Require external source of cholesterol
• Medically important species are facultative
  anaerobes
• Laboratory setting production of small colonies
  on specialized agar after 3-4 days
• Central portion penetrates the agar
• Periphery spreads to adjacent surfaces
• fried-egg appearance

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Mycoplasma pneumoniae

• Etiological agent for disease known as Primary
  Atypical Pneumonia (Walking Pneumonia)
• Lower respiratory tract infection
• Mode of Transmission person-to-person via
  respiratory droplets
• Epidemiology worldwide distribution, year-round
  infection w/ ? incidence in late fall and winter
• Cases usu. sporadic epidemics do occur among
  individuals in close contact schools, prisons,
  military populations.
• Highest incidence older children, young adults
  (6-20 yoa)

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Mycoplasma pneumoniae

• Pathogenesis
• M. pneumoniae w/ membrane-associated protein, P1,
  cytoadhesion
• Binds sialic acid glycolipids on host cell
  membranes
• Affinity for ciliated bronchial epithelial cells
• Inhibits ciliary action
• Inflammatory response develops in bronchial
  adj. tissues as mucosa desquamates
• Disease is an expression of host IS response
• Organism is shed in saliva several days before
  onset of clinical disease re-infection is common

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Mycoplasma pneumoniae

• Clinical Disease
• Primary Atypical Pneumonia or Walking Pneumonia
• Onset gradual starts w/ non-specific sxs HA
  w/ fever, chills and malaise
• After 2-4 days, dry or scantily productive cough
  develops
• Possible earache
• Chest X-ray reveals patchy, diffuse
  bronchopneumonia involving one of more lobes
• Patients often remain ambulatory thru-out the
  illness
• Complications are rare

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Mycoplasma pneumoniae

• Laboratory Identification/Dx
• Direct microscopic examination of clinical
  material
• Sputum analysis scanty and nonpurulent
• Cultured on special agar, but isolation in 8-15
  days not much of aid in tx decisions
• Staining poor or not at all
• Serological tests (Ab detection by C fixation
  using mycoplasma glycolipid extract Ag) best to
  est. Dx.
• dx made if 4-fold ? in titer between acute
  convalescent samples
• Treatment
• Antibiotic therapy shortens the course of
  disease sxs may only be eliminated gradually,
  though

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Genital Mycoplasma

• Mycoplasma hominis Ureaplasma urealyticum
• Common inhabitants of genitourinary tract,
  particularly in sexually active adults
• Mycoplasma hominis causes postpartum of
  postabortal fever also involved in PID
• Ureaplasma urealyticum common cause of
  urethritis (non-gonococcal, non-chlamydial) in
  ?s involved w/ endometriosis in females and in
  cases of pregnant ?s undergoing premature labor
  of delivering low-birth wt. babies

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Chapter 17 Chlamydia

• Family Chamydiaceae
• Genus Chlamydia
• Species Chlamydia trachomatis
  Chlamydia psittaci Chlamydia
  pneumonia
• General Genus Characteristics
• Small, round-to-oval organisms, vary in size
• Cell envelope consists of 2 lipid bilayers w/
  associated cell wall
• Outer membrane similar to Gram-negative bacteria
• BUT contains no PG and muramic acid NOT present
• Possess ribosomes and synthesize their own
  proteins
• Unique developmental cycle (life cycle)
• Obligate INTRACELLULAR bacterial parasite
• Must live w/in a host cell to survive and
  replicate depends COMPLETELY on host cell for E
  b/c they lack ability to synthesize own E (ATP)

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Chlamydia

• Development (Life) Cycle
• Occurs inside cytoplasmic vacuoles of host cell
• 2 forms Elementary body Reticulate body
• Elementary Body (EB) extracellular and
  infectious tiny, condensed, inert structure that
  can survive extracellular cell-to-cell passage
  initiates infection
• Reticulate Body (RB) intracellular and
  non-infectious (inclusion body)
• EB ? RB ? EB, etc. CYLCE

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Chlamydia

• Development (Life) Cycle (fig 17.3 p. 178)
• EB enters susceptible host cell by
  receptor-mediated phagocytosis
• Facilitated by chlamydial cell membrane proteins
  that function as adhesions, directing attachment
  to host cell glycolipid or glycopolysaccharide
  receptors
• EB, when present w/in phagosomes, prevent
  formation of phagolysosomes (i.e., prevent fusion
  of phagosome and lysosome)
• Protection from enzymatic destruction
• EB ?s into larger structure RB (8 hr. time
  lapse)
• RB is NOT infectious, is metabolically active,
  survives only intracellularly, and is the
  replicating form of chlamydia
• RBs divide by binary fission to fill enlarge
  the vacuole, forming and inclusion body
• After 48 hours, RB multiplication ceases RB ?s
  into smaller, infectious EBs that are NOT able
  to multiply
• EBs are released from host cell by cytolysis,
  resulting in cell death
• Released EBs enter a new host cell and the cycle
  is repeated

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Chlamydia trachomatis

• Etiological agent for non-gonoccocal urethritis
  (NGU) gt m/c STD in the US
• Also causative agent for range of genitourinary
  ocular (eye) infections
• Non-gonnococcal Urethritis (NGU)
• ?s urethra locus of infection
• ?s may present w/ cervicitis (sign of early
  infection) /or urethritis
• Infections often asymptomatic, but communicable
• Contiguous spread may involve epididymis in men,
  and uterine tubes surrounding tiss. in women,
  leading to PID
• Asymptomatic or untreated ? cases ? scarring of
  uterus uterine tubes (chlamydia ascends
  reproductive tract) ? sterility
• Asymptomatic or untreated ? cases ? chlamydia
  ascends reproductive tract to epididymis ?
  potential sterility
• Symptomatic cases similar to infections caused
  by N. gonorrhoea, but incubation is longer (2-3
  wks) and discharge is mucoid w/ fewer pus cells

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Chlamydia trachomatis

• Trachoma ocular infection
• Chronic contagious form of keratoconjunctivitis
• Leading cause of blindness in underdeveloped
  countries tremendous inflammation cant see
  eye
• Transmitted by personal contact (eye epithelium)
• Eye-to-eye via droplets
• Contaminated surfaces touched by hands conveyed
  to eyes
• Flies
• Inflammatory response ? permanent opacities of
  cornea ? distortion of eyelids ? conjunctival
  follicles undergo tissue necrosis ? 2 bacterial
  infection of the eye (opportunistic bacteria) ?
  leads to blindness

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Chlamydia trachomatis

• Lymphogranuloma Venereum (LGV) genital infection
• Transmitted by sexual contact follows genital
  inoculation
• Uncommon in US
• Characterized by transient papules on external
  genitalia
• 1-2 months later gt painful swelling of inguinal
  perirectal lymph nodes dt/ invasion of
  lymphatic circulatory systems
• Adenopathy (lymph node swelling) often
  accompanied by constitutional symptoms
• Inguinal buboes develop
• Large painful lymph nodes in inguinal area
• Lymph nodes suppurate
• Chronic inflammation fibrosis ? extensive
  ulceration and blockage of regional lymphatic
  drainage.

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Chlamydia trachomatis

• Laboratory Identification/Dx
• Cell culture Gold Standard observation of
  inclusion bodies (Reticulate Bodies), or the
  vacuoles, filled w/ Chlamydia in cells scrapped
  from infected tissues
• Serological Tests
• Enzyme immunoassay
• AgAb w/ added dye gt AgAb complex can be
  visualized
• Lights up gt () Chlamydia
• Does not light up gt (-) Chlamydia
• Fluorescent Ab
• Direct Immunofluorescence Format Ab (DFA)
  appearance of apple-green EBs under microscope
• Highly sensitive PCR Amplification DNA/RNA probes
• Treatment Prevention
• Antibiotic therapy
• No vaccine No acquired immunity
• Treat 2º bacterial infection in trachoma
• Proper hygiene sanitation most effective in
  preventing eyes infec.

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Chlamydia psittaci

• Etiological agent of Psittacosis or Ornithosis
• Zoonitic disease
• Transmitted to humans by inhalation of dust
  contaminated w/ respiratory secretions or feces
  of infected BIRDS, esp. parrots
• Affects Lower Respiratory Tract acute onset of
  fever, hacking dry cough, flu-like sxs
• Possible enlargement of liver spleen
• Occupational disease (DVMs, animal handlers) -
  pneumonia

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Chlamydia pneumoniae

• Respiratory pathogen that causes pharyngitis,
  followed by laryngitis, bronchitis, sinusitis,
  interstial pneumonia/pneumonitis
• Significant cause of community-acquired
  respiratory infection worldwide distribution
• Person-to-person transmission usu. thru
  aerosolized respiratory droplets (sneezing)
• Responsible for adult-onset asthma
• Antibiotic therapies are available

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Chapter 18 Mycobacteria

• Genus Mycobacterium
• Species Mycobcaterium tuberculosis
  Mycobacterium bovis
  Mycobcaterium avium-intracellulare (MOTT or
  Atypicals) Mycobacterium
  leprae
• General Genus Characteristics
• Mycobacteria have a high lipid content
• Cell wall is a complex layered complex Gram ()
  w/ a lot of Lipid
• PG skeleton overlayed w/ layers of Lipid (fat)
• 1 lipid Mycolic Acid
• Lipid accounts for 40-60 of dry wt. of cell
• Cell wall composition responsible for
  distinguishing traits
• Acid fastness
• Slow growth
• Resistance to disinfectants, stains, and common
  antibiotics also corrosive action of strong
  acids alkalis drying, but not heat UV rad
• Antigenicity surface glycolipids

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Mycobacteria

• General Genus Characteristics
• Acid-Fast Bacilli
• Ziehl-Neelsen Procedure acid fast stain
  (Carbol-fuchsin) is forced by heat or detergent
  into the cell
• Bacterium resists acid alcohol decolorization
  retains RED color of acid fast stain
• NOT able to be stained by Gram stain reagents
• Waxy cell surface makes bacterium strongly
  hydrophobic
• Slow Growth Rate
• Generation time 18-24 hours compare E. coli _at_
  30 min
• Slow growth rate d/t lipid-rich cell wall

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Mycobacteria

• General Genus Characteristics
• Microscopic Morphological Appearance
• Acid Fast Bacilli (AFB)
• Non-spore former
• Non-motile
• No capsule
• Obligate aerobe
• Mycobacteria are aerobic, slow-growing bacilli
  that possess a high lipid (fat) content.
• Growth Conditions
• Simple growth medium inorganic salts, asparagine
  and glycerol
• Selective media Lowenstein Jensen
  Middlebrook 7H-10 or Middlebrook 7H-11
• Colony Appearance extremely rough/dry colonies
  d/t high lipid content
• Serpentine colonies coiled or winding grow
  parallel to one another form serpentine cords
  Virulence Factor! (not known how it works,
  though)
• Cord factor mycoside (mycolic acid bound to
  CHO) responsible for serpentine cords
  ?-hydroxylated FAs

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Clinical

• Tubercle Bacilli Tuberculosis
• Etiological agents
• Mycobacterium tuberculosis (Human strain)
• Mycobacterium bovis (found in cattle only)
• Epidemiolgy
• Transmission close person-to-person contact via
  inhalation of infectious aerosols (shed by
  coughing)
• Organisms remain viable in the environment for a
  long time d/t resistance to dessication
• Single infected person can pass organism to
  others in an exposed group family, classroom,
  hospital ward.
• High Rates of Infection
• Homeless, recent immigrants, drug addicts, AIDS
  pts
• Nosocomial transmission AIDS pts or multi-drug
  resistant TB

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Clinical

• Tuberculosis
• 1 Tuberculosis Direct Course Infection recent
• 2 Tuberculosis Reactivation or Reinfection
• Activation of a latent infection
• new direct course
• Disseminated Tuberculosis Extrapulmonary
  Tuberculosis non-pulmonary infections

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1 Tuberculosis

• Respiratory disease
• Infections restricted to lung or lower
  respiratory tract
• Mode of Infection
• Inhalation of bacilli
• Phagocytosis by Alveolar Macrophages
• Growth of bacilli intracellularly w/in
  macrophages d/t presence of sulfatides
• Sulfatides component of lipid layered cell wall
• Function inhibit pagosome-lysozome fusion thus
  ? bacterial survival when phagocytized
• Macrophages are generally unable to destroy the
  bacilli thus, bacilli proliferate are carried
  to regional lymph nodes set up additional foci

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1 Tuberculosis

• Mode of Infection
• Exudative Lesions or 1 Lesions early part of
  infection
• Characterized by the presence of PMN leukocytes,
  fluid and inflammation
• Most bacilli growing intracellulary in
  macrophages
• Lesion may heal resorption of
  inflammatory-derived exudate
• Productive Lesions or Tubercles
• 3 4 weeks after infection host develops a
  cellular immunity or allergy to the bacilli
• Large influx of mononuclear cells into lungs ?
  formation of specific infection sites or
  tubercles
• Tubercle or Granuloma solid mass or nodule
• Central core TB bacilli and enlarged
  macrophages
• Outer wall fibroblasts, lymphocytes
  neutrophils
• Tubercle appears as a granular nodule (granuloma)
  hosts mechanism for inhibiting bacillary
  multiplication
• Housed w/in tubercles are Bacilli, which can be
  re-activated
• Tubercles may harbor bacteria indefinitely
• Formation of tubercles or granulomas walls off
  lesions form healthy lung tissue bacilli may
  reside in lung tiss. for rest of ones life

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1 Tuberculosis

• Mode of Infection
• Productive Lesion Expansion
• Neutrophils _at_ lesion site release lysosomal
  enzymes that destroy bacilli, tubercle (necrotic
  tissue) and healthy tissue
• Caseation necrosis semi-solid coagulated mass
  (cheesy-state) of host cells bacilli
• Caseous Lesion 2 fates
• Heal calcification infiltration of fibrous
  tissue (fibrosis) and Ca2 deposits
• Expansion of caseous lesion resulting in
  cavities in the lung after lung clearance of
  necrotic tissue
• Lesion breaks down, caseous material discharged,
  and cavity created that can facilitate spread of
  infection
• Entry of Bacilli into Bloodstream
• Dispersion of bacilli by lymph blood stream
• Lesion expansion involves portal vein
• Infectivity of other organs tissues lungs,
  regional lymph nodes, bone marrow, liver, spleen,
  kidneys, and CNS (meninges)

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1 Tuberculosis

• Note In progressive disease, 1 or more of the
  tubercles may expand, leading to destruction of
  tissue clinical illness
• Ex. Chronic pneumonitis, tuberculous
  osteomyelitis or tuberous meningitis
• Extreme cases Miliary (disseminated) TB active
  tubercle thru-out entire body

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2 Tuberculosis

• Reactivation of bacilli from a earlier or
  existing infection
• ? in IS function allows infection to come up
  again
• Reactivation of a 1 infection 2/3 of all new
  cases of TB
• Residing w/in tubercle or healed 1 lesions are
  dormant bacilli thus, most cases 2 stage of
  TB resulting from re-awakening of the dormant
  lesion
• Bacilli reactivated d/t ? immunological
  capabilities
• Elderly
• Immunosuppressive disease Diabetes, AIDS
• Chronic alcoholism
• Prolonged corticosteroid therapy
• Malnutrition
• Severe stress
• Reinfection of new bacilli from the environment

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Disseminated Tuberculosis

• Extrapulmonary or Nonpulmonary Infections
• Lung lesion ? entry of bacilli into bloodstream
  and lymph system ? possible infection of every
  organ in body (theoretically)
• Organs most commonly involved
• Regional lymph nodes
• Kidneys
• Genital tract
• CNS
• Long bones weight-bearing joints

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Clinical TB

• Early Symptoms non-specific
• Malaise, weight loss, cough, night sweats
• Symptoms of Chronic TB
• Violent coughing, chest pain, greenish or bloody
  sputum, extreme fatigue
• Immunity
• Infection w/ TB bacillis ? delayed
  hypersensitivity reaction (cell-mediated
  immunity) CD4 T-cells
• Mycobacterium Ag Tuberculin
• Resistance to TB
• Ability of macrophages to kill bacilli or inhibit
  growth
• T-cell sensitivity NOT life-long to Tuberculin Ag

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Clinical Tests for TB

• Tuberculin Testing Skin Sensitivity Test
• (see fig. 18.7 fig. 18.8 p.789)
• Tuberculin Ag Purified Protein Derivative (PPD)
  from mycobacteriums cell wall Mantoux Test
• Inject 5 Tuberculin units of PPD intradermally in
  forearm
• Measure size of induration (hardness) after 48-72
  hours
• Degree of induration _at_ site of injection is an
  indication of the individuals present or past
  association w/ TB
• An area of redness w/ swelling gt10mm in dia gt
  ()
• Positive Reaction or Skin Test () gt shows that
  the person has been exposed to the disease and it
  progressed at least to the 1 stage indication
  of prior contact w/ mycobacterial protein, but
  NOT necessarily active disease
• Test measures the highly specific delayed-type
  hypersensitivity that develops against the
  tubercle bacilli

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Clinical Tests for TB

• Roentgenography Chest X-rays
• Tubercular infections produce abnormal radiopaque
  (appears white) patch
• Shows the initial pulmonary nodule (healing
  tubercle) and fibrosis the classic Ghon complex

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Clinical Tests for TB

• Laboratory Detection
• Microscopy
• Clinical source of infecting bacilli
• TB sputum or lung secretions
• Disseminated TB CSF, urine, synovial fluid,
  feces
• Direct identification of AFB
• Ziehl-Neelson stain
• Fluorescent Acid-fast stain
• Culture for accurate species ID, but slow
  growth!!
• Selective media Lowenstein Jensen or
  Middlebrook 7H10 or 7H11
• 3 ? 4 weeks for colony growth
• Biochemical test production of niacin, catalase
  and nitrate reductase gt another 6 weeks
• Rapid means of Species Identification
• Nucleic acid probes DNA probes
• Chromatographic analysis of cell wall lipids by
  HPLC (high performance liquid chromatography)
  BEST!

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Treatment for TB

• No hospitalization
• Past-pts are quarantined (sanatoriums)
• Prolonged antibiotic therapy
• 6 month drug regimen w/ combined antibiotics to
  avoid drug resistance
• Long period WHY?
• Many organisms are intracellular
• Rate of metabolism is slow
• Chemotherapeutic drug does not easily penetrate
  the fibrotic or caseous lesions
• Outbreaks of multi-drug resistant TB
• 1990 ? Present
• Primarily seen w/ AIDS pts, homeless in NYC
  Miami
• 6 month regimen of combined antibiotics with
  additional ones for 1st 2 months

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Prevention of TB

• Family members or recently diagnosed cases
  receive isoniazid (INH) chemoprophylaxis
• Tuberculin skin testing screening hospital
  workers
• Vaccine attenuated Bacille Calmet-Guerin (BCG)
  mutant strain isolated from M. bovis (cow
  species)
• Vaccination of young children in countires w/
  high rates of TB offers 20-80 protection for
  several yers
• NO vaccination used in US b/c it induced a ()
  tuberculin test
• Control extremely difficult!
• Slow/chronic disease difficult to isolate people
  until months or years after infection
• Patients non-compliance w/ therapy immigrants,
  homeless, substance abuse, mental illness or
  socioeconomic problems

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Tubercle Bacilli

• Mycobacterium bovis
• Pathogen associated w/ cattle
• Transmission Human infection
• Ingested contaminated milk
• Infection - 1lesions of bone marrow of hip, knee
  or vertebrae
• Inhaled pulmonary infection tuberculosis
• Eradicated in United States
• Destruction of tuberculin () cows
  pasteurization of milk

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Nontuberculos Mycobacterioses or Atypical
Mycobacterioses

• MOTT Mycobacteria other than M. tuberculosis
  M. bovis
• M. avium intracellulare Complex (MAI)
• Associated w/ AIDS pts 3rd m/c cause of death
  (opportunistic) d/t organ failure
• Originally associated w/
• Compromised pulmonary function (chronic
  bronchitis)
• Clinically identical to pulmonary TB
• Risk Groups AIDS pts (terminal stages)
• Transmission
• Ingestion of contaminated food or water
• Transmission to humans from environment
• Pathogenesis
• Mycobacteria multiply in lymph nodes ? spread
  systemically
• Organ involvement
• All organs infected bacilli flood blood stream,
  bone marrow, bronchi, intestine, kidney, liver
• Treatment antibiotic therapy
• Prognosis POOR mass bacilli impair organ
  function

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Leprosy or Hansens Disease

• Etiological agent Mycobcaterium leprae
• Acid fast bacillus w/ large amounts of lipid
• Induces hypersensitivity
• Multiplies slowly
• Distinguishing characteristics
• Strict intracellular parasite no growth on
  artificial media (not cultivated in vitro)
• Cultivated in vivo mouse foot pad or armadillos
• Very slow growth generation time 12 days

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Leprosy or Hansens Disease

• Transmission
• Person-to-person spread by inhalation or direct
  contact of lesions
• Inhalation of bacilli onto nasal mucosa
• Direct skin contact (intact skin or penetrating
  wound) w/ respiratory secretions or wound
  exudates
• Pathogenesis
• Entry
• Phagocytosed by Macrophages (bacilli are NOT
  destroyed, though)
• Intracellular survival of bacilli w/in
  macrophages
• Incubation Period 2 5 years may extend to
  20 yrs
• Infection
• Chronic progressive disease of SKIN NERVES
• Early sxs of Leprosy are often associated w/
  anesthesia over an are of the body

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Leprosy

• Indeterminate or Borderline Leprosy
• Initial Symptom
• Few hypopigmented areas of the skin plus a
  dermatitis
• Severe Residual Symptoms
• Damage to the nerves that control muscles of
  hands and feet wasting of hands feet
• Subsequent wasting of muscles loss of control
  drop foot or claw hand
• Disease Progression
• Dependent upon treatment
• Immunological competence of individual
• Incompetent weakened macrophages
• Outcome
• Most individuals recover spontaneously
• Development of either Tuberculoid Leprosy or
  Lephromatous Leprosy

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Leprosy

• 2 Major Clinical Forms
• Tuberculoid Leprosy
• Localized or superficial form
• Symptoms
• 1 3 shallow skin lesions
• Lesions blanched, appear flat, contain few
  bacilli
• Localized areas of anesthesia nerve damage
• Loss of sense, sensitivity, sensation, feeling
• Nerve Damage result of inflammation that occurs
  during a cellular immune response to the bacilli
  in the nerve
• Recovery frequently self-limiting

40
Leprosy

• 2 Major Clinical Forms
• Lepromatous Leprosy
• Most severe, characterized by large nodular
  lesions accountable for disease-associated
  disfiguration
• Lepromas infection sites
• Degrees of Disfiguration
• (Resistance Immunocompetence)
• Maximum Resistance disease affects superficial
  nerve endings related skin areas
• Minimal Resistance organ involvement eyes,
  testicles and bones

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Leprosy

• 2 Major Clinical Forms
• Lepromatous Leprosy
• Early Symptoms
• Small hypopigmented spotty lesions
• numbness hands feet
• Loss of heat cold sensibility
• Muscle weakness
• Chronic stuffy nose
• Thickened earlobes
• Later Symptoms
• Diffuse to nodular lesions (Lepromas)
  granulomatous thickenings result of massive
  intracellular overgrowth enlargement of
  macrophages by bacilli skin nodules w/ millions
  of bacilli
• Lesion Location cooler parts of the body
• Nose, ears, eyebrow, anterior 1/3 of eye,
  peripheral nerve trunks _at_ specific sites elbow,
  wrist, ankle

42
Leprosy

• 2 Major Clinical Forms
• Lepromatous Leprosy
• 2 Symptoms Trauma mutilation to self-sensory
  loss self-mutilation cannot feel anything!
• Untreated Death d/t kidney or respiratory
  failure
• Increased Susceptibility
• Health pre-disposing risk factor inherited or
  acquired defect in cell-mediated immunity
• Living conditions
• Long-term household contact w/ leprotics
• Poor nutrition
• Crowded conditions
• Inadequate hygiene

43
Leprosy

• Diagnosis
• Presence of skin lesions nodules (granulomas)
  consistent w/ clinical disease
• Non-culturable AFB in lesions (nasal discharges,
  tissue samples nodules)
• Neurological evaluation of extremities
• Occurance of anesthesia
• Feather test field dx
• Lepronin skin test no aid in dx
• Lepromatous pts impaired cellular immune
  response will NOT react
• Most individuals test positive to lepronin

44
Leprosy

• Treatment
• Combined antibiotic therapy
• Prevention
• Surveillance of high risk populations to discover
  early cases
• Chemoprophylaxis of healthy persons in close
  contact w/ leprotics
• Isolation of leprosy pts.