Bronchial Visualization of Tetanic Contractions: A Case Report

Background

Tetanus is a potentially fatal but preventable disease. It is caused by the Clostridium tetani toxin, a Gram-positive bacterium that produces spores which can be found in high concentrations in soil and animal excrement [1]. It is estimated that around 1 million cases of Clostridium tetani infection occur around the world each year, causing the deaths of about 60 000 people. Most of these cases occur in Africa and Asia, where numerous programs for prevention and management have been launched. These programs have made great progress, as evidenced by the 95% reduction in incidence and 99% reduction in mortality related to tetanus. These improvements have been possible thanks to increased vaccine use and the improvement of sanitary conditions [2]. Tetanus has increased in our country of Ecuador in recent years with 49, 52, and 61 cases reported in the years 2015, 2016, and 2017, respectively. Up to week 52 of 2018, 68 cases of tetanus were reported, compared to the epidemiological week 52 of 2017, in which 59 cases of tetanus were reported, which shows an increase in the number of cases. The provinces that reported cases were Manabí, Pichincha, Guayas, Esmeraldas, Cotopaxi, El Oro, Orellana, Azuay, Chimborazo, Imbabura, Pastaza, Galápagos, Loja, Napo, and Tungurahua [3] (Figure 1).

Notably, almost all cases of tetanus occur in people who have not been immunized or who have received inadequate immunization.

The average incubation period is between 3 and 21 days, although its duration may be longer in inadequately protected persons. Generally, a shorter incubation period implies greater severity of the disease [4]. The bacteria’s spores transmit the disease. Once in the organism, the spores are converted into vegetative forms that multiply and produce tetanospasmin. This tetanus toxin inhibits the presynaptic release of the neurotransmitter’s GABA (gamma-aminobutyric acid) and glycine, preventing the inhibition of motor neurons. This manifests as an increase in activity and muscle tone, causing spasms, which compromises the autonomic nervous system. In turn, this leads to sympathetic predominance, in which the neurotoxin primarily affects the brainstem and spinal bone marrow through the retrograde axonal transport system [5].

Clinically, tetanus can present in 4 ways: generalized, neonatal, local, and cephalic [6]. The presentation of the generalized form is the most frequent. It is characterized by spasms that start in the masseter muscle or trismus. These then progress to more severe spasms that are terribly painful and include more regions, most commonly affecting the cervical region [7]. During severe episodes, prolonged spasms lead to severe hypoventilation, which may be due to laryngeal spasms that result in sudden airway obstruction. This can lead to episodes of prolonged life-threatening apneas [8]. Furthermore, the rarity of bronchial obstruction or tetanic contractions has not been evidenced by any study.

Patients can also develop autonomic instability, which can contribute to cardiac arrest. As such, it is essential to know how to identify and treat risk wounds and cases of suspected tet-anus by emergency physicians or primary care providers [9]

We present a case of generalized tetanus in which we focus on the bronchial characteristics as evaluated by bronchoscopy performed in the intensive care unit (ICU).

Case Report

A 59-year-old male patient was brought by his family to the emergency department, presenting difficulty in mandibular opening (trismus), neck stiffness, and dysphagia. He disclosed facial trauma. Edema was evidenced and pain referred at the level of the nasal bridge. When reviewing the symptoms, we noticed right facial paralysis. The only significant detail of his medical history was type II diabetes mellitus. The patient did not report having allergies and denied the use of tobacco, alcohol, and drugs. His vital signs were the following: temperature 38.4°C, blood pressure 149/94 mmHg, pulse 89 beats per minute, and respiratory rate 16 breaths per minute. His admission laboratory tests showed leukocytes 8200 mm3 (normal range, 4400 to 11 300 mm3), hemoglobin 12.9 g/dL (normal range, 12 to 16 g/dL), hematocrit 39%, (normal range, 42% to 50%), average corpuscular volume 93 fL (normal range, 80 to 96 fL), mean corpuscular hemoglobin concentration (MCHC) 30.6 g/dL (normal range, 32.2 to 35.5 g/dL), average platelet volume 8.4 fL (normal range, 8.9 to 11.8 fL), monocytes 0.45 per mm3 (normal range, 0 to 0.8 per mm3), eosinophils 0.20 per mm3 (normal range, 0 to 0.45 per mm3), lymphocytes 0.55 per mm3 (normal range, 1.0 to 4.8 per mm3), neutrophils 12.93 per mm3 (normal range, 1.8 to 7.7 per mm3), basophils 0.03 per mm3 (normal range, 0 to 0.2 per mm3), platelets 23 2000 per mm3 (normal range, 150 000 to 450 000 per mm3), red blood cell count 3.74×106/mm3 (normal range, 4.3 to 5.9×106/mm3), monocytes (%) 7.6 (normal range, 5.3 to 12.2), eosinophils (%) 1.6 (normal range, 0.8 to 7), lymphocytes (%) 10.8 (normal range, 21.8 to 53.1), neutrophils (%) 91.3 (normal range, 34 to 67.9), basophils (%) 0.5 (normal range, 0.10 to 1.2), and procalcitonin 0.27 ng/mL (normal range, <0.046 ng/mL).

The patient was hospitalized, and tetanus toxoid was administered as well as antibiotic therapy (cefepime plus vancomycin 1 g intravenous every 12 hours). Symptoms and signs worsened and resulted in acute onset of respiratory failure, severe muscle spasms, and opisthotonos; he was admitted to the ICU. An intermittent positive pressure ventilation (IPPV) mode was initiated with tidal volume (Vt) of 450 mL (8 mL/kg/weight/ideal); inspiratory time (TI) of 1 second; flow of 45 L/minute; positive end expiratory pressure (PEEP) of 5 cmH2O; and respiratory rate (RR) 12–14 beats per minute at 45% FIO2. For the calculation of ideal Vt, the following formula was used: 55.5±2.3 (height in inches – 60) for men. Patient ventilatory parameters were as follows: minute volume (MV) was 8.2 L/min; exhaled Vt was 430 mL; maximum airway pressure (Pimax) was 29 cmH2O; plateau pressure (Ppat) was 22 cmH2O; mean pressure (Pm) was 12 cmH2O; airway resistance (Raw) was 16.2 cm H2O/L/sec, and compliance (CSTA) was 46.7 mL/cmH2O. Blood gas analysis showed a pH of 7.31; pCO2 was 44.8 mmHg; PO2 was 162.8 mmHg; HCO3 was 24.4 mmol/L; base excess (EB) was – 3.4; SO2 was 99%; PAO2/FIO2 was 466. The patient was sedated with midazolam at a dose of 0.3 mg/kg/hour, and received analgesia with fentanyl at a dose of 1.5 mcg/kg/hour, and neuromuscular block with rocuronium bromide at a dose of 0.25 mg/kg/hour; tetanus toxoid, antibiotic therapy as well as immunoglobulin 51.18 IU/kg/weight were also provided.

During his stay in the ICU, the patient presented a thermal boost with leukocytosis, suggestive of a possible new pulmonary condition. Standard chest radiography was performed, which revealed atelectasis at the right basal level, a prominent pulmonary hila, accentuation of the bilateral bronchial vascular plot, and mediastinal widening of probable vascular etiology (Figure 2). A flexible bronchoscopy was performed, and contraction of the bronchial rings was evidenced (Figure 3). A sample was taken by bronchoalveolar lavage. A Gram culture and stain were performed, revealing the presence of large negative bacillus and a polymorphonuclear isolated germ, Klebsiella Pneumoniae, producing extended-spectrum β-lactamases (ESBL). To treat the infectious disease, a broad-spectrum scheme was given with carbapenems and aminoglycosides, which were sensitive according to the antibiogram performed. The patient continued to receive mechanical ventilatory support due to intense spasm of the respiratory tract until he had a cardiorespiratory arrest while in the ICU that did not respond to cardiopulmonary resuscitation.

Discussion

The diagnosis of tetanus is primarily based on clinical findings. It is characterized by hypertonia with muscular contraction or painful spasms [7]. The generalized tetanus in this clinical case was characterized by initial involvement of the head and neck. This patient’s debut was trismus with progression toward cervical musculature expressed by a stiff neck. Among the differential diagnoses of tetanus, pathologies such as drug-induced dystonia, trismus due to dental infection, strychnine poisoning, malignant neuroleptic syndrome, or rigid person syndrome must be excluded [8]. Our patient had symptoms suggesting a clear predominance of muscular respiratory contracture (a severe compromise of smooth bronchial musculature), which we confirmed by means of bronchoscopy.

Additional management complications included aspiration pneumonia, laryngospasm, respiratory insufficiency, paralytic ileus, asystole, and other symptoms [9]. All these complications, if not resolved in a timely manner, can cause death.

Asphyxia is the most frequent cause of death, due to larynx muscle spasms and acute obstruction of the respiratory tract. When the patient requires invasive mechanical ventilation, the prognosis is worse, because the patient will require sedation and non-depolarizing neuromuscular blocking agents [10,11]. Furthermore, autonomic dysfunction and nosocomial infections like nosocomial pneumonia often caused by multi-resistant organisms are usually associated.

This patient was subjected to bronchoscopy due to the probable diagnosis of nosocomial pneumonia. By means of this procedure, the contraction of the bronchial rings and the existence of tetany at the respiratory level were observed; these findings are rarely evident. It is interesting to note that, although in developed countries its incidence is very low, this infection is still an endemic disease in developing countries. Therefore, it is vital to know how to screen for, understand, and treat it.

Furthermore, it is important to emphasize that tetanus is entirely preventable through vaccination. Low and middle-income countries have the highest rates of tetanus mortality; across the world and independent of the age range, tetanus mortality also tends to be higher amongst males than females, probably because of gender-based differences related to health-care seeking behaviors and cord care, occupational hazards, circumcision, and lower vaccination coverage [12] More generally speaking, tetanus deaths are related to inadequate immunization practices and antenatal and delivery care [13,14]. Improved delivery of these basic healthcare services in upper middle-income countries like Ecuador is both possible and desirable as a means to prevent avoidable mortality from diseases like tetanus.

Conclusions

Tetanus is a potentially fatal infectious disease which, during its evolution, creates multiple complications, usually requiring intensive management and care. The diagnosis of this disease is fundamentally clinical. It should always be suspected in patients who present muscle spasms after potential exposure through wounds. A history of incomplete or complete lack of vaccinations is medically significant. Although muscular contractions are widespread, this clinical case is the first to evidence bronchial spams reported and visualized by bronchoscopy.