Chlamydia is a Gram-negative coccoid or ovoid bacterium that is an obligatory intracellular bacterium (it depends on another cell such as the human cell to live); some chlamydiae cause Trachoma (caused by Chlamydia trachomatis) while others cause Pneumonia (caused by Chlamydia pneumonia).
Table of Contents
- Types of Chlamydia species that cause disease in humans (Chlamydia Infections Causes)
- Chlamydia Life cycle
- Chlamydia Characteristics
- Chlamydia Transmission
- Chlamydia Symptoms and Signs
- Chlamydia Diagnosis
- Chlamydia Treatment
- Chlamydia Complications
- Chlamydia Prevention
Types of Chlamydia species that cause disease in humans (Chlamydia Infections Causes)
- Chlamydia psittaci this causes Ornithosis (Psittacosis)
- Chlamydia trachomatis this causes Trachoma
- Chlamydia pneumonia this causes pneumonia
Chlamydia psittaci is a specie of chlamydia that causes Psittacosis or Ornithosis which an infection of birds that can be transmitted to humans (it is a zoonosis). Psittacosis is a respiratory infection that is spread by inhalation of dust containing chlamydia psittaci. It has an incubation period of 1 to 3 weeks and causes Atypical pneumonia.
Chlamydia trachomatis specie is capable of causing different diseases in humans such as Trachoma, Swimming pool conjunctivitis, inclusion-conjunctivitis in Neonates, Lymphogranuloma venereum (a venereal disease) and Non-specific urogenital infections affecting men and women such as cervicitis, urethritis, salpitngitis etc).
List of diseases caused by Chlamydia trachomatis with associated serotypes (serovars)
- Trachoma (Kerato-conjunctivitis) caused by serovars A, B, Ba, and C
- Inclusion conjunctivitis another form of Trachoma caused by serotypes D, Da, E, F, G, H, I, Ia, J and K
- Trachoma causing Urethritis, Cervicitis, Salpingitis, Otitis Media or Pharyngitis caused by serovars B, C, D, E, F, G, H, I, K and L
- Lymphogranuloma venereum ( this is a venereal disease) this is caused by Lymphogranuloma venereum serovars L1, L2, L2a, and L3
This is an acute infection that causes purulent papillary conjunctivitis and affects neonates, children and adults (when it affects adults, it is called swimming-pool conjunctivitis). Newborn children are usually infected during childbirth by the pathogens colonizing the birth canal. If left untreated, it forms a pannus and corneal scarring may occur with blindness following.
Genital infections caused by Chlamydia trachomatis
Chlamydia trachomatis is a sexually transmitted infection (STD) that is responsible for 30 to 60% of cases of non-gonococcal urethritis (NGU) in men. Men usually get infected when they have intercourse with an infected female partner who may not even show symptoms or signs as most women having this infection may show no signs. Apart from urethritis, proctitis, or infections of the genital organs, chlamydia trachomatis is also known to cause pelvioperitonitis and peri-hepatitis.
Lymphogranuloma venereum is also called Lymphopathia venerea or Favre-Durand-Nicolas disease or Lymphogranuloma inguinale (this is different from granuloma inguinale). This infection is mostly found in warm climatic zones of the world. It forms a herpetiform primary lesion at the site of invasion in the genital area that develops into an ulcer inflammation of the lymph nodes affected.
Lymphogranuloma venereum can be diagnosed isolating the proliferating pathogen in cell cultures from specimen obtained from purulent material of the ulcer or matted lymph nodes. Identification of antibodies against the infection can be used for diagnosis too using the complement binding reaction or the micro-immunofluorescence test.
Lymphogranuloma venereum can be treated with Tetracyclines and macrolides.
Chlamydia pneumoniae was formerly named as TWAR chlamydiae (TaiWan Acute Respiratory agent); it causes upper respiratory tract infections and mild pneumonia and also plays a possible role in the pathogenesis of atherosclerotic cardiovascular disease. Chlamydia pneumoniae is pathogenic in humans only and it is responsible for over 60% of chlamydial infections in humans as serological studies revealed that about 60% of adults have antibodies against Chlamydia pneumoniae. This infection is spread by inhalation of aerosol droplets.
List of infections caused by Chlamydia pneumoniae
- Influenza- like infections
- Atypical Pneumonia
Some infections caused by Chhalmydia pneumonia are clinically silent but are frequent.
Chlamydia Life cycle
Chlamydiae have two stages in their reproductive life cycle which include the elementary bodies (EB) stage and the initial bodies (IB) stage. The elementary bodies stage occurs outside the human cell and helps the organisms to survive outside of host cells. The initial bodies (IB) help the organisms to reproduce while inside the host cells. Chlamydia begins infection of a host when the metabolically inactive elementary bodies enter the epithelial tissue, in the host cell, the elementary bodies transform into active reticulate bodies which then multiply and release more elementary bodies when the cell dies after using all of the host cells ATP.
- Chlamydia is another taxon of the Alphaproteobacteria
- Members of this genus are extremely resistant to the cellular defenses
- Chlamydiae are obligate intracellular organisms, which means that they depend on their host cells to multiply and survive
- Sexual intercourse for Chlamydia trachomatis
- Inhalation of infected air droplets for Chlamydia pneumoniae
- Vertical transmission for C. trachomatis causing inclusion conjunctivitis in newborn
Chlamydia Symptoms and Signs
- Conjunctivitis (Redness of the eyes)
- Genital infections may show signs and symptoms of infections such as discharge, pains and ulcerations
- Respiratory difficulty
- Lymphadenitis (swollen lymph nodes)
- Identification of organisms under the microscope in smear material using direct immunofluorescence
- Direct identification by means of amplification of a specific DNA sequence in smear material and urine
- Growing in special cell cultures
Treatment involves the use of appropriate antibiotics
- Blindness from Trachoma
- Prostatitis from Chlamydia trachomatis infections
- Epididymitis caused by Chlamydia trachomatis infections
- Massive perinatal infection of Chamydia trachomatis may cause interstitial chlamydial pneumonia in neonates
- Abstinence or protected sexual intercourse
- Prompt treatment to prevent complications such as blindness
- Practice good hygiene
Dr. Brown is the founder of Jotscroll, he is a Medical Doctor, Entrepreneur, and author. Dr. Razi Brown holds a medical degree from the University of San Diego. He has invested in many startups and is currently working on his fifth book to be published in the upcoming year.