Diphtheria, Term Paper Example

Diphtheria is a highly infectious and acute disease spreading through droplet infection, mostly affects the nose and throat portions through contaminated objects and foods (Kasper and Fauci, 2010). The dangerous substances, namely the toxins produced by the bacteria, Corynebacterium diphtheria, spread from the blood stream to various organs like heart and brain causing considerable damage. With crowded environments, poor hygiene and immunization absence as prime risk factors, the symptoms of Diphtheria usually prevail for two to five days following the contact with the associated bacteria (Wheeler, 2006). Characterized through sore throat, fever, and pseudo membrane on the tonsils, pharynx and nasal cavity, the milder form of this disease may be restricted only towards the skin portions. However, less common consequences such as myocarditis and peripheral neuropathy may also be witnessed within 10% of the cases. Historically speaking, diphtheria had immensely eradicated amongst the various industrialized nations by widespread and developed vaccinating measures (Morgan, 1995). For instance, in the United States of America around 52 cases of diphtheria had visualized during the years of 1980 and 2000. The count had found to be minimized at a significant rate to three cases from 2000 to 2007 owing to the continued usage of Diphtheria-Pertussis-Tetanus (DPT) vaccine suggested amongst high risk and school aged children. Periodic vaccine boosters can be implicated for adults as the usefulness of vaccine decrease with age and without regular re-exposure. Though the disease found its prevalence in various countries, it had known to exert minimal effects in United States and other European countries. Children under the age group of 5 years and adults around 55-60 years old may be specially characterized to be under the risk of contracting the infection. Furthermore, individuals sustaining within crowded and unclean premises, under nourished environments and improper immunization schedules are much prone to the risk of Diphtheria (Wheeler, 2006).

Causative Agent

Diphtheria, bacterial infection caused by Corynebacterium diphtheriae, is the prime organism causing the infection. This pathogenic bacterium also known as Klebs-Loffer Bacillus is a gram positive pleomorphic organism possessing no arrangement. Different strains of this bacterium infect the nasopharynx or skin portions and lead to pharyngitis, fever, neck swelling and skin lesions. Toxic strains of this bacterium secrete potent exotoxins that get distributed to the distant organs through the circulatory systems causing congestive heart failure and paralysis. This non-motile, non-capsulated club shaped and, lysogenic toxic strains are one amongst the family of corynebacteriophages, which carry structural gene for the disease toxin (Fiebach et al., 2007).

Based on the colony morphology, the bacteria can be classified in to numerous biotypes (Mitis, Intermedius and Gravis). Furthermore, the sensitivity of corynebacteriophages governs the lysotypical classification of the organism. Regardless of their individual potency in causing the disease, all the bacterial strains need nicotinic and pantothenic acids for survival. However, some of them require thiamine, biotin and pimelic acid as nutritional supplements. For obtaining, optimal production of diphtheria toxin, the medium should be necessarily supplemented with aminoacids through deferral process (Kasper and Fauci, 2010).

Clinical and Psychological Aspects of Diphtheria

Marked through, the range of, localizations and relatively, high proportion of relevant toxic diphtheria in the stomatopharynx and diversified croup, diphtheria presents, with numerous clinical aspects in infants and adults. The gravest forms of this strain are fairly complex for clinical recognition and carrying out early diagnosis may rest on offering pronounced signs of intoxication, tonsil edema and mucosa in the stomatopharyngeal region. Besides, pannicular patches at the tonsils regions can also be considered as signs of clinical aspect. Sample of tissue from the infected wound portion and passing it for laboratory testing can ensure a predetermined check for the diphtheriae toxin affecting skin. Painful swallowing perceptions, hoarseness, sore throat, complex breathing with characteristic nasal discharge, fever, child, enlarged glands and malaise are certain pivotal clinical aspects associated with the disease (Morgan, 1995).

Certain types of disease may infect skin, resulting in typical pain, redness and swelling. Ulcerous tissues enclosed through a gray membrane can also be the clinical symptom in cutaneous diphtheria. Infected and unaware patients are some of the carriers for the disease as they can spread the infection without gaining knowledge of being sick. Offering well-balanced diet, undertaking effective medical supervision with vaccinations may help in minimizing the effect of the disease to a considerable extent.

History of Diphtheria

Diphtheria, also known as “Strangling Angel of Children” had dreaded to be the most common cause of illness amongst infants less than 3 years of age. The name of the disease had taken its origins from the Greek word “diphtheria” representing leather by a French practitioner, Pierre Bretonneau in 1826. The leathery, sheath like membrane that develops on tonsils, nose and sore throat offers the characteristic name. As a consequence of serious, frequent and large-scale outbreaks during 1735 to 1740 in New England and its victims as many as 80% of infants below 10 years of age, the disease had gained its name as the most dreadful amongst others. Disease statistics represent that, in the years of 1920, an estimated number of 100,000 to 300,000 of diphtheria cases in United States of America with 15,000-20,000 attributed deaths. The origin of diphtheria appears to be associated with poor, dirty and stagnant water and bacteria spreads intimately through airborne particle from the diseased carrier sneezing or coughing.

Genetics of Diphtheria

Different research reports explain the genetic construction, expression and receptor-specific selective toxicity of bacterial toxin. Expression of biologically active chimeric IL-2 toxin necessitates the fusion of modified gene coding IL-2 with a truncated diphtherial toxin gene. The toxin-hormone chimeric gene targets the fusion protein expression and retains the activity of ADP-ribosyl transferase. Although the fusion protein is non-toxic for Chinese hamster ovary or African green monkey kidney (CV-1) cells, it is effective for MSH receptor-positive human malignant melanoma (NEL-M1) cultured cells. The DNA sequence of the bacteria plays a major role in estimating 25-residue leader peptide besides matured protein that is presumably involved in secreting toxin. Carrying out various studies and understanding their concepts effectively may help in offering basis for the application of recombinant DNA technological methods to the diphtheria study. In addition, this may help in developing innovative, new and genetically modified toxin forms applicable for the construction of various classes of immunotoxins.

Diagnosis of Diphtheria

Different research reports explain the genetic construction, expression and receptor-specific selective toxicity of bacterial toxin. Expression of biologically active chimeric IL-2 toxin necessitates the fusion of modified gene coding IL-2 with a truncated diphtherial toxin gene. The toxin-hormone chimeric gene targets the fusion protein expression and retains the activity of ADP-ribosyl transferase. Although the fusion protein is non-toxic for Chinese hamster ovary or African green monkey kidney (CV-1) cells, it is effective for MSH receptor-positive human malignant melanoma (NEL-M1) cultured cells. The DNA sequence of the bacteria plays a crucial role in estimating 25-residue leader peptide besides matured protein that may be presumably involved in secreting toxin. Carrying out various studies and understanding their concepts may help in offering basis for the application of recombinant DNA technological methods to the diphtheria study. In addition, this may help in developing innovative, new and genetically modified toxin forms applicable for the construction of various classes of immunotoxins.
Treatment and Management of Diphtheria

Individuals suffering with Diphtheria disease, one amongst the most dangerous diseases, can be protected through childhood vaccinations. Avoiding dangerous health consequences and administering anti-toxins through intramuscular or intravenous (IM or IV) routes may also aid witnessing significant results. Antibiotics such as Penicillin and Erythromycin play crucial roles in eliminating the bacterial organisms from the respiratory tract and various other sites terminating carrier state. Effective treatment measures aid in preventing complications associated to airway obstruction (Kasper and Fauci, 2010).

Comprehensive supportive care together with psychological support is highly needed for Diphtheria and the following measures aid in its effective management:

• Stress on the necessity for droplet precautions. This may assist in preventing the spread of the disease. Following proper disposal measures for nasopharyngeal secretions of the patient and maintaining preventive measures till the twonegative nasopharyngeal cultures-a week following the drug therapy discontinuation. Treatment of infected individuals, with anti-toxin through controversial, may help in obtaining beneficial outcomes (Morgan, 1995).
  Suggesting the patient’s family to receive toxoid preparations of diphtheria, if they have not immunized and offering drugs as well as pharmacological therapies can aid in managing the disease symptoms considerably (Kasper and Fauci, 2010).
• Undergoing eye and skin tests prior to theadministration of anti-toxin help in estimating the sensitivity. Careful monitoring of respiration, particularly amongst laryngeal diphtheria patients (when they had exposed to high-humidity environments) and watching the indication for airway obstruction may help in offering emergency life support along with intubation and tracheotomy (Fiebach et al., 2007).
• Treating the diphtheria carriers with antibiotics help in clearing their systems through bacterial killing (Marguiles, 2005).

Infants and individuals possessing the signs of diphtheria need to be hospitalized for treatment with isolations in intensive care units (ICU). This is highly necessary as the infections may spread easily to any non-immunized individuals.

Pathogenesis and Specialized Clinical Issues

Susceptible individuals may possess toxin diseased bacilli in the nasopharynx. The bacteria produce toxins which inhibit cellular protein synthesis. This appears to be responsible for localized tissue destruction and membrane formation. Toxins formed at the membrane sites get absorbed into the blood stream and distributed towards other body parts. Clinical complications linked with non-toxin producing diphtheria organisms are milder. However, toxins responsible for myocarditis and neuritis may also cause low platelet counts (thrombocytopenia) and proteinuria manifestations (Morgan, 1995). The incubation period for diphtheria range from 2-5 days and, it may involve almost every mucous membrane. For clinical issues, it is safer and convenient to segregate diphtheria into various manifestations based on disease site. These include (Fiebach et al., 2007):

• Anterior Nasal Diphtheria

The disease onset is perfectly indistinguishable from the fact of common cold and may be mostly characterized through mucopurulent nasal secretions possessing mucus and pus. Upon the nasal septum, a white membrane may be mostly witnessed owing to apparent poor systematic toxin absorption. Antitoxin and antibiotic therapy may help in rapid termination of the disease (Morgan, 1995).

• Pharyngeal and Tonsillar Diphtheria

The most common sites of the disease include pharynx and tonsils. Infection at the site may be usually associated with systematic and substantial toxin absorption. Following the 2-4 days of the incubation period, bluish-white membrane extends in varying size through a small patch on the tonsils enclosing most of soft plate. Patients possessing severe disease may gain marked edema at the anterior neck and submandibular areas exhibiting characteristic bull-neck indication (Wheeler, 2006).

• Laryngeal and Cutaneous Diphtheria

The clinical issue that had associated with this diphtheria involves airway obstruction, barking cough, coma, fever, hoarseness and death. Myocarditis, Neuritis and other clinical complications are highly frequent in Diphtheria and the disease severity increases when the toxin gets absorbed at the tissues and sites distant from the invasive sites (Marguiles, 2005).

Public Health for Diphtheria

Diphtheria, an acute bacterial disease affecting tonsils, throats, nose and skin portions, may be passed from person to other through droplet method. More particularly, breathing in the bacteria after an infected person had coughed, sneezed and laughed may lead to breathing complications, heart failure, paralysis and death. DTap, Td and, Tdap are the different forms of vaccines developed against diphtheria (Morgan, 1995). Around four doses of DTap in children at 15months of age and a Tdap booster dose at an age 11 and 12 years assists in offering protection amongst infants. Adults possess tetanus/diphtheria (Td) booster every 10 years following the primary series had completed. Individuals with 18-64 years of age need a one-time dose of Tdap for gaining protection against pertussis and diphtheria. Nevertheless, the recommended dose of Tdap must be replaced with Td at an interval of less than 2 years as suggested by the practitioner, though not required. Active immunization for the previously immunized individuals must be offered with a booster dose of antibiotics or DTP vaccine, whilst the non-immunized patients may be introduced to primary vaccination series. Benzyl penicillin at 600,000 units amongst children with less than 6 years of age and erythromycin about 125mg for 6 hours a day (children with less than 2 years old) can help in offering positive prophylaxis for the disease. Regardless of disease nature, food handlers, child carers and, nursing professionals must be advised not to attend the schools till the proven condition may be bacteriological negative. Identifying the toxin strains, isolating culturally negative bacterium and, using antibiotic prophylactic measures may aid in effective clinical management of the disease.

References

Marguiles, P. (2005). Diphtheria: Epidemics, Deadly Diseases and Throughout History. New York: The Rosen Publishing Group.

Morgan, W. (1995). Diphtheria. United States of America: B. Jain Publishing Group.

Fiebach, N.H., Barker, N and Burton, J. (2007). Principles of Ambulatory Medicine. New York: The Heinemann Publishers.

Wheeler, B.S. (2006). Trends in Diphtheria Research. London: SAGE Publications.

Kasper, D.L and Fauci, A.S. (2010). Harrison’s Infectious Diseases. United States of America: The Rosen Publishing Group.