Mycoplasma, Ureaplasma, and Chlamydia

Describe the transport requirements of M. pneumoniae

-Do not allow swab or specimen to dry out -Place immediately into transport media •TSA with bovine serum albumin •2SP Broth with calf serum •Shepard's 10B Broth

Signs and Symptoms of M. pneumoniae infection

-Insidious onset -Fever and cough usually present; may be sore throat, nasal congestion; 50% have a productive cough. - Patients "feel like they're getting a cold"; ESR is usually high -WBC - usually elevated; 50% are16-20,000/L. -Cold agglutinins - 50% will be Pos at 2-4 weeks after onset; persists ~6 weeks.

What are the Mycoplasma and Ureaplasma Pathogens?

-Mycoplasma pneumoniae (pathogen) -M. hominis (controversial pathogen) -Ureaplasma urealyticum (controversial pathogen) -U. parvum (controversial pathogen)

What 3 tests are used to confirm identification of Mycoplasma pneumoniae?

1)Hemadsorption Test for M. pneumoniae 2)Tetrazolium Reduction Test 3)Epifluorescent procedure

Identify the following bacterium and specimen pairing that is mismatched (specimen not appropriate for isolation). A) Chlamydia (Chlamydophila) psittaci: Fecal swab B) Chlamydia trachomatis: First voided urine C) Chlamydia trachomatis: Endocervical swab D) Chlamydia pneumonia: Throat swab or sputum

A) Chlamydia (Chlamydophila) psittaci: Fecal swab Chlamydophila psittaci is the new taxonomic classification for Chlamydia psittaci. This bacterium is found naturally in psittacine birds and other avian species. Human infection, psittacosis, is a result of contact with pet birds, or from occupational contact in poultry farming or processing. Inhalation of the organisms from aerosols, fecal material, or feather dust causes a respiratory infection and the specimen of choice is a throat swab or sputum.

Which is the most reliable for the detection of Mycoplasma pneumonia in serum and for the confirmation of diagnosis? A) EIA testing and direct antigen testing B) Cold agglutinin testing using Group O RBCs C) Culture on SP4 glucose broth with arginine D) Complement fixation

A) EIA testing and direct antigen testing The cold agglutinin test is nonspecific and time consuming, and therefore, outdated. Although M. pneumonia can be grown on artificial media, many specimens fail to grow, and growth can take up to 3 weeks. CF tests are not as sensitive or specific as EIA tests Direct antigen assay by immunofluorescence is speciifc but has a sensitivity at least two orders of magnitude below DNA amplification methods. While PCR is the most sensitive method, it may detect the presence of M. pneumonia in the absence of infection. Adults may fail to produce an IgM response especially in recurrent infections, so the best confirmatory approach is a combination of EIA and direct antigen testing

Chlamydia trachomatis infections have been implicated in: A) LGV and conjunctivitis B) gastroenteritis and urethritis C) neonatal pneumonia and gastroenteritis D) neonatal meningitis and conjunctivitis

A) LGV and conjunctivitis Chlamydia trachomatis is a well-known cause of sexually transmitted infections, including urethritis and cervicitis, as well as inclusion conjunctivitis and pneumonia in neonates. It also causes trachoma and lymphogranuloma venereum [Murray 2013, p383]

Which organism typically produces "fried-egg" colonies on agar within 1-5 days of culture from a genital specimen? A) Mycoplasma hominis B) Borrelia burgdorferi C) Leptospira interrogans D) Treponema pallidum

A) Mycoplasma hominis Genital mycoplasmas (M. hominis and Ureaplasma urealyticum) are grown on specific agars. M. hominis is grown on "M" agar containing arginine and phenol red. Colonies of mycoplasma are 50-300um in diameter and display a "fried-egg" appearance with red holes. U. urealyticum is isolated from genital specimens on "U" agar (containing urea and phenol red), then subcultured to A7/A8 agar. Colonies of Ureaplasma are small and golden brown on A7/A8 agar.

Ureaplasma urealyticum is difficult to grow in the laboratory on routine media because of its requirements for: A) sterols B) horse blood C) ferric pyrophosphate D) surfactant such as Tween 80

A) sterols Ureaplasma urealyticum, like other Mycoplasma, lacks a cell wall and possesses an extremely small genome. As a result, this organism has limited biosynthetic capability and fastidious growth requirements. Culture medium should contain serum (provides sterols), growth factors such as yeast extract, and a metabolic substrate. [Mahon 2015, p559]

A 29-year-old man is seen for recurrence of a purulent urethral discharge 10 days after the successful treatment of culture proven gonorrhea. The most likely etiological agent of his urethritis is: A) Mycoplasma hominis B) Chlamydia trachomatis C) Trichomonas vaginalis D) Neisseria gonorrhoeae

B) Chlamydia trachomatis Up to 1/3 of patients with Neisseria gonorrhoeae infection are also-coinfected with Chlamydia trachomatis. Patients with identified infection with one organism are usually treated for both infections. [Mahon 2015, p9033]

Primary atypical pneumonia is caused by: A) Streptococcus pneumoniae B) Mycoplasma pneumoniae C) Klebsiella pneumoniae D) Mycobacterium tuberculosis

B) Mycoplasma pneumoniae A common cause of respiratory tract illness, M. pneumoniae, generally causes a self-limited infection (3-10 days) and usually does not require antibiotic therapy. M. pneumoniae can be cultured from the upper respiratory and lower respiratory tracts onto specially enriched (diphasic) media, but is most frequently diagnosed by the change in antibody titer from acute to convalescent serum using EIA or other serological methods.

Psittacosis is transmissible to man via contact with: A) insects B) birds C) cattle D) dogs

B) birds Chlamydophila psittaci, the agent of psittacosis, is transmitted to humans via inhalation, of dried exrement, urine, or respiratory secretions from specific birds (parrots, parakeets, macaws, cockatiels, etc. [Murray 2013, p387]

Which is the *test of choice* for the confirmation of *Chlamydia trachomatis* infection in urine? A. Enzyme immunoassay antigen testing B. PCR molecular testing C. Culture using McCoy and Hela cells D. Microimmunofluorescence (MIF) test

B. PCR molecular testing EIA and MIF tests detect antibodies to Chlamydia trachomatis, but may also detect antibodies that cross react with other organisms, and are performed on serum. Cell culture is time consuming and dependent on the quality of the specimen. PCR is both sensitive and specific and may be performed on urine

The *manganous chloride-urea test* is used for the identification of which organism? A. Mycoplasma pneumoniae B. Ureaplasma urealyticum C. Bacillus cereus D. Borrelia burgdorferi

B. Ureaplasma urealyticum U. urealyticum is the only human mycoplasma that hydrolyzes urea. The manganous-chloride-urea test utilizes manganous chloride (MnCl2) forming manganese oxide, which is insoluble and forms a dark brown precipitate around the colonies. The reaction is observed under a dissecting microscope and is a rapid test for the identification of U. urealyticum

A 42-year-old woman is admitted to the intensive care unit with hypoxemic respiratory failure and pneumonia in August. She was well until 2 days prior to admission when she developed fevers, myalgias, and headache. She works in a poultry processing plant and is originally form El Salvador. She has been in the United States for 15 years. She has no major health problems. Her PPD was negative upon arrival to the United States. Several other workers have been ill with a similar illness, although no one else has developed respiratory failure. She is currently intubated and sedated. Her oxygen saturation is 93% on an FiO2 of 0.80 and positive end-expiratory pressure of 12cm H2O. On physical examination, crackles are present in both lung fields. There is no cardiac murmur. Hepatosplenomegaly is present. Laboratory studies reveal a mild transaminitis. Influenza nasal swab is negative for the presence of influenza A. Which of the following tests is most likely to be positive in this patient? A) Acid fast bacilli stain and mycobacterial culture for Mycobacterium tuberculosis B) Blood cultures growing S. aureus C) Microimmunofluorescence testing for Chlamydia psittaci D) Urine Legionella antigen E) Viral cultrues of bronchoscopic samples for influenza A

C) Microimmunofluorescence testing for Chlamydia psittaci This patient is likely suffering from pneumonia due to Chlamydia psittaci. This organism is a relatively rare cause of pneumonia, with only about 50 confirmed cases yearly in the US. Contrary to common belief , the organism is not limited to psittacine birds (parrots, parakeets, cockatiels, macaws), but any bird can be infected including poultry. Most infections are seen in owners of pet birds, poultry farmers, or poultry processing workers, and outbreak of pneumonia have been seen in poultry processing facilities. Untreated psittacosis has a mortality of as high as 10%. The illness presents with nonspecific symptoms of fevers, chills, myalgias, and severe headache. Gastrointestinal symptoms with hepatosplenomegaly are also common. Severe pneumonia requiring ventilatory support can occur, and other rare manifestations include endocarditis, myocarditis, and neurologic complications. The current diagnostic tool of choice is the microimmunofluorescence test, which is a serologic test. Any titer greater than 1:16 is considered evidence of exposure to psittacosis, and paired acute and convalescent titers showing a fourfold rise in titer are consistent with psittacosis.

A 22-year-old college student comes to your office because of a cold and respiratory symptoms of about 12 days'duration that do not seem to be lessening in intensity. He is anorexic and tired. His respiratory rate is 24/minute, and he has a cough productive of small amounts of white sputum, but no hemoptysis or pleuritic chest pain. His chest x-ray shows infiltration in the right lower lobe. He has a leukocytosis of 18,000 and his cold agglutinin titer is elevated. The organism that is the likely cause of this illness is: A) Leptospira B) Influenza virus C) Mycoplasma pneumoniae D) Legionella spp. E) Coxiella burnetti

C) Mycoplasma pneumoniae Mycoplasma pneumoniae pneumonia occurs predominantly in adolescents and young adults and also in elderly adults. It begins insidiously with fever, cough, and scant white sputum, but not hemoptysis. The cold agglutinin antibodies are elevated in this infection, usually in about one half of cases and not in the other infections. The chest x-ray is usually positive in the infiltrate is interstitial, mainly in the lower lobe on one side; occasionally, it involves both lungs. (Braunwald, 15/e, pp1073)

Which organism fails to grow on artificial media or in cell cultures? A) Chlamydia trachomatis B) Neisseria gonorrhoeae C) Treponema pallidum D) herpes simplex virus

C) Treponema pallidum Chlamydia trachomatis, Neisseria gonorrhoeae, and herpes simplex virus can all be isolated in culture. Direct culture of Treponema pallidum on artificial media has not been achieved. dark-field microscopy and serological techniques are used to diagnose T. pallidum infection. [Murray 2013, p535]

A 20-year-old woman is 36 weeks pregnant and presents ofr her firest evaluation. SHe is diagnosed with C. trachomatis infection of the cervix. Upon delivery, what complication is her infant most at risk for? A) Jaundice B) Hydrocephalus C) Hutchinson triad D) Conjunctivitis E) Sensorineural deafness

D) Conjunctivitis Congenital infection from maternal transmission can lead to severe consequences for the neonate; thus, prenatal care and screening for infection are very important. C. trachomatis is associated with up to 25% of exposed neonates who develop inclusion conjunctitivitis. It can also be associated with pneumonia and otitis media in the newborn. Pneumonia in the newborn has been associated with later development of bronchitis and asthma. Hydrocephalus can be associated with toxoplasmosis, Hutchinson triad, which is Hutchinson teeth (blunted upper incisors); interstitial keratitis, and eigth nerve deafness, is due to congenital syphilis. Sensorineural deafness can be associated with congenital rubella exposure Treatment of C. trachomatis in the infant consists of oral erythromycin [Harrison's principles of Internal Medicine, Chapter 213]

What Specimen Collection sites/types are appropriate for M. homis and Ureaplasma urealyticum?

•Collect urethral, cervical or vaginal swabs •Prostatic secretions •Semen •Urine •Placenta or amniotic fluid •Fetal tissues •Fallopian tubes

Pathogenicity of Mycoplasma pneumoniae

•Organism attaches to epithelial cells in respiratory tract and multiplies -Does not penetrate the cell •2-3 week incubation period •Generally self-limiting; resolution of symptoms in 3-10 days without antibiotics •Even if treated, the organism is not eradicated from the Respiratory Tract

Mycoplasma virulence factors

•P50 & P100 are surface localized polypeptides that also function in adherence •Phospholipase enzymes (A1, A2, & C) -Localized in the plasma membrane -Hydrolyze phospholipids -Release arachidonic acid -May be responsible for fetal death

List the alphabet soup of culture media for M. hominis and Ureaplasma urealyticum

•U-9 Urease Media •S-2 Boston Broth •SP-4 with urea (for Ureaplasma) or arginine (for M. hominis) •Shepard's A7 media

What bacteria am I? •Require sterols in the form of cholesterol; no other bacteria require it. •Facultatively anaerobic

Mycoplasma

What genus am I? •Smallest organism capable of self-reproduction outside a host. •Some species are found as normal flora of the mouth (gingival area)

Mycoplasma

This image depicted two chest x-rays, which revealed pathologic changes in a patient's lung fields due to a condition known as mycoplasma pneumonia, caused by a _______________ _______________ bacterial infection. Note on the anteroposterior (AP) view on the left, the generalized infiltrate permeating both lung fields, and consolidation in the region of the right lower lobe, as well as bilateral hilar adenopathy. In the left lateral view on the right, you can see that the consolidation occupied more of the posterior aspect of the lung fields, almost obliterating a view of the spinal column.

Mycoplasma pneumoniae

What am I? •Never part of normal flora. •Disease - Primary Atypical Pneumonia. Also called "Walking pneumonia". •10-30% of atypical pneumonia is caused by M. pneumoniae •Chest X-ray looks bad; infiltration in 2-5 lobes.

Mycoplasma pneumoniae

What bacteria characteristially appears as "fried egg" colonies on solid media?

Mycoplasma pneumoniae

What causes "walking pneumonia"?

Mycoplasma pneumoniae

Syndrome Epididymitis

Pathogens Chlamydia trachomatis Enterobacteriaceae M. tuberculosis N. gonorrhoeae Pseudomonas spp

Syndrome Urethritis

Pathogens Chlamydia trachomatis H. influenzae H. parainfluenzae HB-S N. gonorrhoeae Ureaplasma urealyticum

Species Mycoplasma pneumoniae

Primary Site of colonization Respiratory Tract: POS Genitourinary tract NEG Metabolization of: Glucose POS Arginine NEG Pathogenicity POS

M. pneumoniae Diagnostic Test Serologic studies

Sensitivity 55-100% Specificity 55-100%

M. pneumoniae Diagnostic Test Respiratory PCR

Sensitivity 65-90% Specificity 90-100%

M. pneumoniae Diagnostic Test Respiratory culture

Sensitivity <60% Specificity 100%

What is this organism?

Ureaplasma urealyticum

How is the bacteria Mycoplasma pneumoniae transmitted?

aerosols

So called _____________ _______________ usually presents as a less dramatic, milder form of illness compared with disease caused by the common bacterial pathogens, which is generally more rapid in onset and more sever in intensity.

atypical pneumonia

Do mycoplasma have a rigid cell wall?

nope

How is Mycoplasma pneumoniae transmitted?

respiratory droplets

A previously healthy 19-year-old man presents with several days of headache, cough with scant sputum, dyspnea, and fever of 38.6C. On examination, pharyngeal erythema is noted, and lung fields showed scattterred wheezes and some crackles. Chest radiograph shows bilateral peribronchial insterstitial infiltrates. His hematocrit is 24.7% down form a baseline masure of 46%. The only other laboratory abnormality is an indirect bilirubin of 3.4. A peripheral smeasl reveals no abnormalities. A cold agglutinin titer is measured at 1:64. What is the most likely infectious agent? A) Coxiella burnetti B) L. pneumophila C) Methicillin-resistant S. aureus D) M.pneumoniae E) S. pneumoniae

D) M.pneumoniae This patient presents with symptoms of atypical pneumonia, and the most common causative organism for atypical pneumonia is M. pnuemoniae. Pneumoniae caused by Mycoplasma occurs worldwide without a specific seasonal preference. M pneumoniae is a highly infectious organism and is spread by respiratory droplets. It is estimated that approximately 80% of individuals within the same family will experience the infection once one person becomes infected. Outbreaks of M. pnuenmoniae also occur in institutional settings, including boarding schools and military bases. Clinical manifestations of M. pneumoniae typically are pharyngitis, tracheobronchitis, wheezing, or nonspecific upper respiratory infection. Cough is present and, although often extensive, is typically nonproductive. Examination typically demonstrates wheezing or rales in approximately 80% of patients. The most common xray findings are bilateral peribrohcial pnuemonia with increased interstitial markings. Lobar consolidation is uncommon. Definitive diagnosis requires demonstration of M. pneumoniae nucleic acids on PCR of respiratory secretions or performance of serologic testing

Organism Mycoplasma hominis

Disease Acute pyelonephritis, bacterial vaginosis, pelvic inflammatory disease, postabortion bacteremia Reservoirs Humans Vector & Mode of Transmission Sexual contact vertical transmission in utero or intra-parturition

Organism Chlamydia pneumoniae

Disease pneumonia, bronchitis, sinusitis, pharyngitis Reservoirs Humans Vector & Mode of Transmission inhalation of infectious aerosols

Organism Ureaplasma urealyticum

Disease urethritis, epididymo-orchitis, urinary calculi, abortion, chorioamnionitis Reservoirs Humans Vector & Mode of Transmission sexual contact in utero peripartum vertical transmission

Organism Chlamydia trachomatis

Diseases Endemic trachoma, inclusion keratoconjuctivitis, urethritis, epididymitis, endometritis, salpingitis, pneumonia lymphogranulorum venerum Reservoirs Humans Vector & Mode of Transmission Sexual contact hand-eye contact insect vector infected birth canal

Organism Mycoplasma pnuemoniae

Diseases Tracheobronchitis, pnuemonia, pharyngitis, extrapulmonary complications, meningencephalitis, urethritis Reservoirs Humans Vector & Mode of Transmission contact with infectious aerosols or fomites