Serologic Procedures Are of Little Help in the Diagnosis of Whooping Cough
Seismologic procedures are of little help in the diagnosis of whooping cough because a rise in tighter of most antibodies does not occur until at least the third week of illness. It is difficult to distinguish abortive or mild cases of pertussis from bronchitis caused by other agents except by bacteriologic means. On the other hand, paroxysmal coughing may be associated with pulmonary lesions such as allergic bronchitis, atypical pneumonia, or cystic fibrosis. Pertussis-like illnesses, associated with lymphocytes, have been reported in rhinovirus infections. Treatment.
Mild cases of pertussis require only supportive treatment. Specific therapy of severe whooping cough has been disappointing despite the in vitro susceptibility of B. pertussis to various antimicrobial agents and the protective effect of passively administered antibodies in experimental disease. Antimicrobials. Several antimicrobial drugs have significant in vitro activity. pertussis. Agents that readily eradicate the organisms in human disease may shorten the course of the illness if given in the catarrhal or early paroxysmal stages.
In the established paradox-small stage the organisms can also be readily eliminated by antimicrobials, but the course of the iPhess is Unaltered Even h' the Redwingstage the use of drugs is justified to render the patient noninfectious. In a recent study, erythromycin, oxytetracycline, and chloramphenicol were shown to be more effective in eliminating organisms than ampicillin, lin, an often recommended agent. Based on drug safety and efficacy, either erythromycin or tetracycline is the drug of choice. The daily dose for each is 5to mg. per kilogram of body weight given in four divided doses.
The organism is eliminated after a few days of therapy, but because bacteriologic relapse may occur, treatment should be continued for ten to fourteen days. Immunotherapy. Hyperimmune human gamma globulin is often used in the therapy of immunized patients, particularly small infants. The usual dose is 1.25 or 2.5 ml. intramuscularly for three successive days. Supportive Therapy. Particularly in the young infant, supportive measures combined with careful nursing care are of paramount importance. Specific attention must be devoted to the maintenance of proper water and electrolyte balance, adequate nutrition, and sufficient oxygenation. Constant alertness for the presence of secondary infectious complications such as pneumonia is required, and appropriate therapy should be promptly instituted upon discovery. Prevention.
The great communicability of whooping cough, particularly during the first few weeks of illness, makes it desirable to isolate the patient for four to six weeks, or, ideally, until cultures are negative. Unfortunately, the diagnosis is usually not made until the end of the catarrhal stage, and by the spread of the disease has already occurred. Exposed susceptibles should be isolated from social groups until it is determined whether the disease is present,t. of hyperimmune gamma globulin intramuscularly, the dose to be repeated in five days. Recent studies have suggested that erythromycin may be effective in prophylaxis against pertussis in exposed, susceptible persons. Active immunization. There is little doubt that the fall in the incidence of whooping cough in the very young is directly related to widespread immunization with suitable, killed suspensions of B. pertussis.
The highest risk of serious or-morbidity and mortality is in the young infant. Women of child-bearing age generally do not have significant levels of protective antibody in their sera, and consequently, the newborn is not protected by maternal antibodies. Cian is markedly impaired. Rarely, cortical degeneration occurs, but the exact pathogenesis of the encephalopathy. Is unknown. Serous meningitis with lymphocytosis of the cerebrospinal fluid has been described. Localized areas of emphysema and atelectasis generally return to normal after the disease has run its course, and thorax and interstitial emphysema are infimMently seen.
The major came of death in whooping cough is compensating imewanneM or bronchopneumonia caused by bar bacteria or viruses. Besides, secondary bacterial otitis media occurs frequently. Diagnoses. There is little difficulty in making the clinical diagnosis of whooping cough in a patient who, after a variable period of coryzal symptoms, develops paroxysmal coughing with a terminal inspiratory whoop. Toward the end of the catarrhal stage, or early in the spasmodic phase, leukocytosis often occurs. In contrast to the leukocytosis found in most bacterial diseases, the predominating cell type is the mature small lymphocyte. Characteristically the leukocyte count ranges from 15,000 to 30,000 per cubic millimeter, and 80 percent of the cells are small lymphocytes. However, the leukocyte count either may be nor-mal or may reach a level greater than 100,000 per cubic millimeter. Polymorphonuclear leukocytosis suggests a secondary bacterial complication.
Difficulty in recognizing whooping cough occurs in the catarrhal stage, in abortive or lizliV cases, and young infants. Epidemiologic awareness may suggest the possibility, but microbiologic identification of the organisms is required. During the early stages of whooping cough, B. pertussis can be isolated from approximately 90 percent of patients. By the third or fourth week of illness, the organism can be recovered in only 50 percent of cases, and in the convalescent stage, it is unusual to obtain a positive culture. Therefore, active immunization is begun as early as is commensurate with the production of a satisfactory immune response.
At present, it is recommended that the infant receive three injections of pertussis vaccine at one-month intervals beginning at 6 to12 weeks of age. Each injection provides four NIH* units. The NIH unit is based upon the ability of a vaccine to protect mice against a stand-ard intracerebral infection. The pertussis sus-pension is usually incorporated into a triple vac-cine with alum-precipitated diphtheria and tetanus toxoids (DPT). Administration of pertussis vaccine to those over six years of age is not generally recommended because of an appearance in-creased incidence of untoward reactions.