Introduction
Among the most serious bacterial illnesses affecting people is diphtheria. Generally, it impacts the upper respiratory system, resulting in the production of pseudomembranes and occasionally asphyxia and death. Diphtheria toxin-induced widespread symptoms might make the disease more difficult to treat. Skin conditions and aggressive viruses, such as endocarditis, are other illness types. The bacteria Corynebacterium diphtheriae, a type of bacteria belonging to the class Actinomycetes, is the cause of diphtheria. Certain variants of C. diphtheriae carry lysogenized corynephages on their chromosomes, which carry the diphtheria toxin. Although there is a diphtheria vaccine, hundreds of cases are still recorded each year, and global healthcare system disruptions can swiftly lead to massive epidemics.
Diagnostic Tests
Microbiologic laboratory diagnosis of harmful C diphtheriae in throat or lesion samples is necessary for the diagnosis of diphtheria. A number of materials may be utilized for isolation and identification: Tellurite agar by Tinsdale, Mueller-Miller, or Loeffler (Centers for Disease Control and Prevention). Pharyngeal glands or their sites are swabbed using sanitized cotton-tipped cotton buds. Nasopharyngeal samples can be obtained for culture by inserting calcium alginate probes into both nasal passages (Centers for Disease Control and Prevention). Diphtheritic lesions frequently have a pseudomembrane covering them, so it would be necessary to gently uncover the lesion’s surface before using the tool to swab. Depending on the trends of carbohydrate fermentation and hemolysis after first collection, C. diphtheriae can be classified as belonging to the mitis, intermedius, or gravis biotypes.
Numerous in vitro and in vivo tests are used to assess the toxicity of C. diphtheriae strains. Elek testing is the most widely used in vitro test for toxigenicity. The foundation of this testing is the simultaneous spread of antitoxin and diphtheria neurotoxin in an agar medium (Centers for Disease Control and Prevention). A toxin-antitoxin precipitin band that forms can be used to identify the generation of diphtheria virus within 20 to 48 hours (Centers for Disease Control and Prevention). As an option, several eukaryotic cell types are susceptible to diphtheria bacteria, allowing for the use of in vitro tissue culture techniques for pathogen identification. C. diphtheriae may be detected using other tests like the polymerase chain reaction and the matrices-aided laser desorption of flight spectrometry (Centers for Disease Control and Prevention). Such tests are viewed as supplementary, but when done in isolation, they do not prove toxin generation. The nares and oropharynx, as well as any mucous or dermal lesions, can be used as sources for culture samples. If at all feasible, materials should be sourced from either the membrane’s inside or a section of it.
If samples are collected before the individual starts receiving antibiotic therapy, they have a higher chance of being culture-positive. In the U.S., respiratory diphtheria is infrequent, yet the outbreak can lead to increased outbreak risks (Centers for Disease Control and Prevention). Diagnostics for other infections should be taken into consideration since infections with other viruses may provide a clinical picture comparable to diphtheria (Centers for Disease Control and Prevention). In addition to infections including Epstein-Barr, CMV, influenza, and herpes.
Symptoms
While the virus can be treated in the initial stages without severe symptoms, the range of affected organs must be considered. The respiratory system, which comprises organs that are essential for breathing, is where microbes most frequently cause infection. Fatigue, a throat infection, a low-grade fever, and enlarged neck nodes are a few of the symptoms that might result from bacteria entering and attaching to the wall of the respiratory system. The bacterium produces a toxin that destroys healthy respiratory cells. The dead tissue quickly turns into a dense, gray covering that can accumulate in the nasal passages in two to three days. This dense, gray covering is referred to by doctors as a pseudomembrane. It can obstruct the tonsils, throat, vocal cords, and nasal passages, making it more challenging to inhale and ingest. Harm to the heart, kidneys, nerves, and blood vessels may result from the poison entering the bloodstream.
Treatment
The standard treatment is timely injection of a diphtheria antiviral drug accompanied by antibiotic treatment. Certain epidemiological studies indicate that it is 97 percent successful (Chaudhary and Pandey).In order to reduce the number of potential contacts, it is vital to separate every case and take appropriate safety measures. The plasma of horses that have had a diphtheria toxin vaccination often contains diphtheria antitoxin, or DAT (Chaudhary and Pandey). As a result, it works to neutralize diphtheria toxin in circulation rather than poison attached to cells. Due to this, it is practical to deliver antitoxin quickly following the creation of the presumptive diagnosis, even before its microbiological verification (Chaudhary and Pandey). Antibiotics are given to patients in order to eradicate harmful microorganisms.
Penicillin and erythromycin are among the most commonly prescribed medications, and they are typically used for at least two weeks. The primary treatment for diphtheria is penicillin, with erythromycin advised in cases of intolerance. In practice, both antibacterial medicines are successful in treating diphtheria (Hennart et al.). Penicillin, erythromycin, and other antibacterial drugs can occasionally be combined to create multidrug-resistant isolates of C. diphtheriae, which have been observed to be less susceptible to these medications or completely resistant to them (Hennart et al.). A nasopharyngeal and throat test should be performed after the antibiotic treatment has finished working. Additional antibiotic therapy for 10 days might be administered if the samples are still abnormal. The virus’s resistance to antibiotics has raised a lot of concern. The first instance of erythromycin-resistant, multi-drug resistant C diphtheria was initially documented in Canada. (Chaudhary and Pandey)
Diphtheria vaccination starts early in infancy in order to ensure the protection of the child’s health. Beginning with the first dosage in the sequence, which is typically administered in the second month after birth, three consecutive dosages are administered in intervals of 4 to 8 weeks (Chaudhary and Pandey). The third dosage is preceded by the fourth dosage, which is administered around a year following the final main vaccine. The CDC advises adults to obtain a higher dose of vaccination every 10 years since the efficacy of immunizations steadily declines over time (Chaudhary and Pandey). A tourist visiting an epidemic region, including Asia, Africa, Central and South America, Russia, and Eastern Europe, should receive an extra dose of diphtheria vaccine.
Conclusion
Hence, diphtheria is one of the most dangerous bacterial diseases that may affect people. Primarily, it affects the upper respiratory system, causing pseudomembranes to be produced and, on rare occasions, suffocation and death. A few signs that bacteria may penetrate and attach to the respiratory system’s wall include fatigue, a throat infection, a low-grade fever, and swollen neck nodes. There are several tests that may be used for isolation and identification, including the Elek test, Mueller-Miller, Loeffler, and Tinsdale’s Tellurite agar test. The recommended course of treatment includes prompt injection of a diphtheria antiviral medication and antibiotic therapy. In addition to using penicillin as one of the major treatments, there is a diphtheria vaccine that reduces the risks of morbidity and death.
Works Cited
Centers for Disease Control and Prevention. “Clinical Features of Diphtheria.” CDC, 2020.
Chaudhary, Anmol, and Shivlal Pandey. Corynebacterium Diphtheriae. StatPearls Publishing, 2020.
Hennart, Melanie, et al. “Population genomics and antimicrobial resistance in Corynebacterium diphtheriae.” Genome Medicine, vol. 12, no. 1, 2020, pp. 1-18.