Abnormal Development - Bacterial Infection
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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|
Some Recent Findings
|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.
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. See also the listeriosis review article and the Guinea pig placenta listeria model 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.
- ingestion of contaminated food
- colonization of the intestine
- intestinal translocation
- replication in the liver and spleen
- either the resolution of infection or spread to other organs resulting in a systemic infection
The bacterium spirochete Borrelia Burgdorferi causes Lyme disease. Infection can be through the blood by tick bite.
- Links: CDC (USA) - Lyme Disease
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
BCG vaccination is not recommended for general use in the Australian population.
BCG is recommended for:
- Aboriginal neonates in areas of high incidence of TB (e.g. Northern Territory, Far North Queensland, northern areas of Western Australia and South Australia)
- 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
- neonates born to parents with leprosy or a family history of leprosy
In addition to these recommendations BCG may be considered in the following:
- Children over 5 years who will be travelling or living in countries or areas with a high prevalence of TB for extended periods
- 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)
(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.
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)
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.
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 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.
- 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
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.
Australian NHMRC Recommendations
The Australian NHMRC (1988) recommends neonates be assessed for follow-up care under the following conditions.
- 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.
- <pubmed>19250368</pubmed>| Journal of Obstetrics and Gynaecology of Canada 2007;29:35-44)." (text from BMJ 2007;334(7587):224
- <pubmed>12648833</pubmed>| PLoS One
- <pubmed>16225680</pubmed>| PMC1266370 | BMC Microbiol.
<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 Jan2006 "bacterial infection" 547,445 reference articles of which 45,020 were reviews.
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- CDC (USA) Public Health Training Network Epidemiology and Prevention of Vaccine-Preventable Diseases (viewable Webcasts requires Media Player) | Advisory Committee on Immunization Practices (ACIP) Recommendations
- Royal College of Obstetricians and Gynaecologists (UK) Infection and Pregnancy - study group recommendations (Jun 2001)
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Cite this page: Hill, M.A. (2021, July 24) Embryology Abnormal Development - Bacterial Infection. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Abnormal_Development_-_Bacterial_Infection
- © Dr Mark Hill 2021, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G