Difference between revisions of "Abnormal Development - Bacterial Infection"

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:'''Links:''' [[Abnormal_Development_-_Listeria|Listeria]] | [http://www.ncbi.nlm.nih.gov:80/books/bv.fcgi?db=Books&rid=mmed.section.973 Medical Microbiology - Listeria]
:'''Links:''' [[Abnormal Development - Listeria]] | [http://www.ncbi.nlm.nih.gov:80/books/bv.fcgi?db=Books&rid=mmed.section.973 Medical Microbiology - Listeria]
== Lyme Disease ==
== Lyme Disease ==

Revision as of 12:04, 19 November 2011

Educational Use Only - Embryology is an educational resource for learning concepts in embryological development, no clinical information is provided and content should not be used for any other purpose.


The spirochete bacteria treponema pallidum, the cause of syphillis.

The variety of bacterial infections that can occur during pregnancy is as variable as the potential developmental effects, from virtually insignificant to major developmental, abortive or fatal in outcome. Some bacteria are common and are part of the normal genital tract flora (Lactobacillus sp), while other bacterial infections are less common or even rare and initially infect/transmit by air or fluids through the different epithelia (genital tract, lungs, gastrointestinal tract).

Note that some infections may have historic or alternative common names, for example Pertussis "whooping cough".

Bacterial Links: bacterial infection | syphilis | gonorrhea | tuberculosis | listeria | salmonella | TORCH | Environmental | Category:Bacteria
Environmental Links: Introduction | low folic acid | iodine deficiency | Nutrition | Drugs | Australian Drug Categories | USA Drug Categories | thalidomide | herbal drugs | Illegal Drugs | smoking | Fetal Alcohol Syndrome | TORCH | viral infection | bacterial infection | fungal infection | zoonotic infection | toxoplasmosis | Malaria | maternal diabetes | maternal hypertension | maternal hyperthermia | Maternal Inflammation | Maternal Obesity | hypoxia | biological toxins | chemicals | heavy metals | air pollution | radiation | Prenatal Diagnosis | Neonatal Diagnosis | International Classification of Diseases | Fetal Origins Hypothesis

Some Recent Findings

  • Tuberculosis (TB) during pregnancy[1] This BJOG paper describes a study which highlights lack of awareness about TB in pregnancy. The number of women who die from TB during pregnancy is increasing in the UK. TB has been classified as a priority infectious disease, and TB incidence in the UK is now higher than that in most western European countries. "All 229 of eligible UK hospitals participated (between August 2005 and August 2006), representing 100% coverage of women giving birth in the UK. During this period, a total of 33 women were diagnosed with TB during pregnancy. All of these women were non-white. Researchers found that TB in pregnancy in the UK appears to be exclusively limited to ethnic minority women and almost exclusively to those born outside the UK.The authors noted that screening for TB during pregnancy, while recommended, does not seem to be undertaken routinely. This may contribute to a delay in diagnosis."
  • Antibiotics during pregnancy[2] "Macrolides or clindamycin during the second trimester of pregnancy to women at risk of preterm births can lower the risk, a new systematic review and meta-analysis by Canadian researchers indicates. But the study also found that giving metronidazole alone in the second trimester is linked with a greater risk of preterm birth in the high risk population. The study's authors, from the University of Montreal and Laval University, Quebec, say that delivery before 37 weeks' gestation complicates between 7% and 11% of all pregnancies, is the leading cause of perinatal morbidity and mortality, and is responsible for high healthcare costs"
  • A universal vaccine for serogroup B meningococcus[3] "Meningitis and sepsis caused by serogroup B meningococcus are two severe diseases that still cause significant mortality. To date there is no universal vaccine that prevents these diseases. In this work, five antigens discovered by reverse vaccinology were expressed in a form suitable for large-scale manufacturing and formulated with adjuvants suitable for human use. The vaccine adjuvanted by aluminum hydroxide induced bactericidal antibodies in mice against 78% of a panel of 85 meningococcal strains representative of the global population diversity."
  • Optimal timing of ampicillin administration to pregnant women for establishing bactericidal levels in the prophylaxis of Group B Streptococcus [4] "Bactericidal levels of ampicillin in the cord blood are rapidly achieved within 30 minutes of administration of ampicillin to the mother. The increase in the ratio of cord to maternal serum ampicillin levels is directly related to time, suggesting a decrease in the clearance of ampicillin in the newborns as compared to the mothers. The cord blood ampicillin concentration exceeds the maternal concentration and both continue to be above the minimal bactericidal concentrations at 5.6 hours after administration."

Neisseria Gonorrhea

Neisseria Gonorrhea, arrowed within a cell (diplococci) and extracellular (pleomorphic) (Image CDC)
The gram-negative bacterium Neisseria gonorrhoeae causes the disease Gonorrhea which is a sexually transmitted disease (STD). Maternal infection increases the risk of premature birth and ophthalmia neonatorum (infantile purulent conjunctivitis).

A recent paper has described in the rat mother to the fetus during pregnancy, suggesting this as a model for human transmission.[5]

Links: Abnormal Development - Gonorrhea

Listeria Monocytogenes

Listeria monocytogenes bacteria (Image CDC)

The bacterium Listeria monocytogenes is the pathogenic form of the 7 listeria species. Infection is generally through ingestion of organisms in contaminated food. Maternal symptoms may be mild, fetal effects can range from insignificant through to major abnormalities. Maternal treatment relates to potential developmental effects. Pregnancy greatly increases the risk of listeriosis, with pregnant women about 60% of all cases (male and female) aged 10 to 40 years. Similar effects are seem in other mammalian species.[6] See also the listeriosis review article[7] and the Guinea pig placenta listeria model[8] Generalized suppression of immunity during pregnancy is suggest to have a role in susceptibility, though recent results in a mouse model suggest that susceptibility can occur very early in a pregnancy and may relate to enteric carriage rate.[9]


  1. ingestion of contaminated food
  2. colonization of the intestine
  3. intestinal translocation
  4. replication in the liver and spleen
  5. either the resolution of infection or spread to other organs resulting in a systemic infection

Links: Abnormal Development - Listeria | Medical Microbiology - Listeria

Lyme Disease

Borrelia burgdorferi, spirochete (or "corkscrew-shaped" bacteria) (Image CDC)

The bacterium spirochete Borrelia Burgdorferi causes Lyme disease. Infection can be through the blood by tick bite.

Links: CDC (USA) - Lyme Disease


Mycoplasma in respiratory epithelium (M, mycoplasma; m, microvillus; C, cilia, EM Image CDC)

Mycoplasmas come in many different varieties, occur as part of the normal human flora, and lack a bacterial cell wall. Infection is generally through the female genital tract.

Links: NCBI Bookshelf Medical Microbiology - Mycoplasma | CDC Mycoplasmas: Sophisticated, Reemerging, and Burdened by Their Notoriety


Treponema pallidum (scanning EM, Image CDC)
The bacterium Treponema pallidum causes syphilis which is a sexually transmitted disease (STD). Infection can lead to congenital infection with abortion, prematurity, neonatal death or multiple system abnormalities.

Links: Abnormal Development - Syphilis | CDC (USA) Fact Sheet - STD and Pregnancy

Mycobacterium Tuberculosis

Mycobacterium-tuberculosis.jpgMycobacterium Tuberculosis (scanning EM, Image CDC)
Robert Koch (1843 - 1910) Discoverer of Mycobacterium tuberculosis, the organism that causes tuberculosis and was awarded the Nobel Prize in Physiology or Medicine in 1905.

The gram-positive bacterium Mycobacterium tuberculosis causes the disease Tuberculosis (TB) usually initially infecting the lungs. The infection can cross the placenta to infect the fetus infecting many different systems (liver, bones, kidneys, spleen, gastrointestinal tract, skin, lymph nodes).

More than two billion people, one third of the world's total population, are infected with TB bacilli, an airborne infectious disease that is preventable and curable.

The Bacille Calmette-Guérin (BCG) vaccine was first used in 1921 as a vaccine for tuberculosis disease and also used in some countries to prevent childhood tuberculous meningitis and miliary disease.

Extensively drug-resistant tuberculosis (XDR-TB2) is a highly drug-resistant strain subset of MDR-TB ([#MDR-Tuberculosis multidrug-resistant TB]) that have significantly worse outcomes, has now been reported in more than 50 countries. (WHO data)

Multidrug-resistant tuberculosis (MDR-TB) is defined as resistance to the two most powerful first-line anti-TB drugs (isoniazid and rifampicin).

Extensively drug-resistant tuberculosis (XDR-TB2) is defined as MDR-TB plus resistance to the most powerful second-line anti-TB drugs (any fluoroquinolone and any of the three injectable drugs: amikacin, capreomycin and kanamycin).


WHO Report 2007 - Global tuberculosis new cases 2007.jpg

Australian Recommendations

BCG vaccination is not recommended for general use in the Australian population.

BCG is recommended for:

  1. Aboriginal neonates in areas of high incidence of TB (e.g. Northern Territory, Far North Queensland, northern areas of Western Australia and South Australia)
  2. neonates and children 5 years and under who will be travelling or living in countries or areas with a high prevalence of TB for extended periods
  3. neonates born to parents with leprosy or a family history of leprosy

In addition to these recommendations BCG may be considered in the following:

  1. Children over 5 years who will be travelling or living in countries or areas with a high prevalence of TB for extended periods
  2. Health care workers (HCWs) who may be at high risk of exposure to drug resistant cases.

(Text Source: Communicable Diseases Intelligence Volume 30 Number 1, March 2006 - The BCG vaccine: information and recommendations for use in Australia)

Links: Abnormal Development - Tuberculosis


(Greek, melis = distemper of asses, oeidēs, resemblance, and osis, a suffix indicating an abnormal condition or disease. The bacteria Burkholderia pseudomallei is normally found in soil surface layers and in muddy surface waters.

  • 1912 - Alfred Whitmore, a British pathologist serving in Burma, and his assistant C. S. Krishnaswami first described melioidosis. The infection became known as Whitmore’s disease.
  • 1925 - Ambrose T. Stanton and William Fletcher identified Burkholderia pseudomallei as the infection’s causative agent, renamed the infection melioidosis because of its clinical resemblance to glanders. Glanders is an infectious disease that is caused by another bacterium Burkholderia mallei.

Links: Queensland Health | CDC - Etymologia: Melioidosis

Bacterial Meningitis

Neisseria meningitidis (arrowed, Image CDC)

The bacterium Neisseria meningitidis or Haemophilus influenzae type B (Hib) can cause the disease bacterial meningitis.

Hib immunization for infants and children are generally recommended.

Recently a universal vaccine for serogroup B meningococcus has been developed (See meningococcal vaccine 2001[10])

Haemophilus influenzae (bright green immunofluorescence, Image CDC)

Links: CDC (USA) - Meningococcal Disease | Medline Plus - Meningitis |


The bacterium Bordetella pertussis can cause the disease Pertussis (Whooping Cough) can lead to infant mortality.

May 2005 - First Combination Vaccine Approved to Help Protect Adolescents Against Whooping Cough USA Food and Drug Administration has approved booster immunization against pertussis (whooping cough) in combination with tetanus and diphtheria for adolescents. Pertussis is a highly contagious bacterial disease. (FDA 03 May 2005)

Links: CDC (USA) - Pertussis | Medline Plus - Pertussis | Pertussis Vaccination: Use of Acellular Pertussis Vaccines Among Infants and Young Children Recommendations of the Advisory Committee on Immunization Practices (ACIP) |


Salmonellosis is the infection caused bacterial genus Salmonella, these are mainly associated with foodborne transmission from contaminated animal–derived meat and dairy products. Though infection can also occur after handling pets, particularly reptiles like snakes, turtles and lizards.

Links: MedlinePlus - Salmonella | CDC - Salmonellosis

Staphylococcus aureus

Staphylococcus aureus (scanning EM, Image CDC)

Staphylococcus aureus a gram-positive bacterium commonly present (25% of healthy people and animals) on the skin and nasal surfaces, no vaccines are available. Strains of this bacteria can produce toxins related to food poisoning and be resistant to various antibiotics.

Methicillin-resistant Staphylococcus aureus (MRSA) bacteria are resistant to various antibiotics including Methicillin, there are other strains which are resistant to specific antibiotics (vancomycin).

About 2% of Staphylococcus aureus produce a toxin Panton-Valentine leucocidin (PVL) which can be fatal in neonates.

Links: CDC (USA) - Staphylococcus | CDC (USA) - emerging infectious diseases | Medline Plus - Staph aureus food poisoning | Medical Microbiology - Staphylococcus

Bacterial Vaginosis

Bacterial vaginosis (gram-stained vaginal smear)[11]
Lactobacillus, gram-positive rods among squamous epithelial cells and neutrophils in vaginal smear (Image CDC)
  • Bacterial vaginosis imbalance of the normal vaginal flora (more anaerobic bacteria and less normal gram-positive bacteria Lactobacillus sp).
  • Maternal infection is associated with a variety of pregnancy abnormalities including preterm birth and poor perinatal outcome.[12]

Smear Image Links: L. crispatus | L. crispatus | non-L. crispatus with thin lactobacilli | non-L. crispatus with thin lactobacilli | mixture non-L. crispatus with L. crispatus | mixture non-L. crispatus with L. crispatus | irregular-shaped Gram positive rod | irregular-shaped Gram positive rod | mixture Lactobacillus and bacterial vaginosis-associated | mixture Lactobacillus and bacterial vaginosis-associated | bacterial vaginosis | bacterial vaginosis
Links: Menstrual Cycle - Histology | Histology - Gram Stain | Bacterial Vaginosis | CDC (USA) Fact Sheet - Bacterial Vaginosis

Gram Stain

Bacterial staining procedure named after Hans Christian Gram (1853 - 1938). Generally divides bacteria into either:

Gram-positive bacteria purple crystal violet stain is trapped by layer of peptidoglycan (forms outer layer of the cell).

Gram-negative bacteria outer membrane prevents stain from reaching peptidoglycan layer in the periplasm, outer membrane then permeabilized and pink safranin counterstain is trapped by peptidoglycan layer.

Links: Histology Stains | Medical Microbiology - Gram stain procedure

Australian NHMRC Recommendations

The Australian NHMRC (1988) recommends neonates be assessed for follow-up care under the following conditions.

(see the NHMRC WWW Page)
  • Birthweight less than 1500g or gestational age less than 32 weeks
  • Small-for-gestational-age neonates
  • Perinatal asphyxia
  • Apgar score less than 3 at 5 minutes
  • clinical evidence of neurological dysfunction
  • delay in onset of spontaneous respiration for more than 5 minutes and requiring mechanical ventilation
  • Clinical evidence of central nervous system abnormalities ie., seizures, hypotonia
  • Hyperbilirubinaemia of greater than 350umol/l in full term neonates
  • Genetic, dysmorphic or metabolic disorders or a family history of serious genetic disorder
  • Perinatal or serious neonatal infection including children of mothers who are HIV positive
  • Psychosocial problems eg., infants of drug-addicted or alcoholic mothers.


  1. <pubmed>19250368</pubmed>
  2. <pubmed>19250368</pubmed>| Journal of Obstetrics and Gynaecology of Canada 2007;29:35-44)." (text from BMJ 2007;334(7587):224
  3. <pubmed>16825336</pubmed>
  4. <pubmed>16458647</pubmed>
  5. <pubmed>10456962</pubmed>
  6. <pubmed>20885996</pubmed>
  7. <pubmed>12648833</pubmed>| PLoS One
  8. <pubmed>15871123</pubmed>
  9. <pubmed>20885996</pubmed>
  10. <pubmed>11734711</pubmed>
  11. <pubmed>16225680</pubmed>| PMC1266370 | BMC Microbiol.
  12. <pubmed>16460868</pubmed>


<pubmed>16374219</pubmed> <pubmed>16085020</pubmed> <pubmed>15784499</pubmed> <pubmed>15861401</pubmed> <pubmed>12648833</pubmed> <pubmed>10816189</pubmed> <pubmed>6293753</pubmed>


<pubmed>16460868</pubmed> <pubmed>16825336</pubmed> <pubmed>16458647</pubmed> <pubmed>15871123</pubmed> <pubmed>12781402</pubmed> <pubmed>11734711</pubmed> <pubmed>10456962</pubmed>

Search Pubmed

Search Jan2006 "bacterial infection" 547,445 reference articles of which 45,020 were reviews.

Search PubMed: embryonic bacterial infection | prenatal bacterial infection | maternal bacterial infection

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Cite this page: Hill, M.A. (2021, September 28) Embryology Abnormal Development - Bacterial Infection. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Abnormal_Development_-_Bacterial_Infection

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