Pakistan reports Naegleria fowleri survivor
Pakistan reports Naegleria fowleri survivor
1 of only 8 reported laboratory-confirmed survivors worldwide
Karachi, Pakistan has been a hot spot for primary amebic meningoencephalitis (PAM) caused by Naegleria fowleri since the first case was reported in 2008.
Since that time, more than 160 cases have been confirmed in Pakistan. Some 400 cases have been reported worldwide.
Seven reported survivors globally were classified as confirmed through 2019, until now.
In a recent issue of the journal, Emerging Infectious Diseases, authors report on the eighth survivor case.
A 22-year-old man sought care at a secondary-care hospital in Karachi on June 17, 2023, with initial symptoms of fever, drowsiness, and vomiting. He had no history of recreational water sports or swimming. His pulse rate was 105 beats/min, temperature 38.8°C, and blood pressure 121/78 mm Hg. His oxygen saturation was 95% in room air, and he had no respiratory distress. His Glasgow coma score was 11/15; he had neck rigidity, bilateral downgoing planters, and tonic-clonic seizures. Results of laboratory testing were unremarkable except an elevated leukocyte count, 19.3 × 109 cells/mL (reference range 4–10 × 109 cells/mL). We made a provisional diagnosis of acute meningoencephalitis and began empirical therapy with intravenous meropenem (2 g/12 h), intravenous vancomycin (1 g/12 h), intravenous dexamethasone (4 mg/8 h), and sodium valproate (500 mg/12 h).
On the same day, we transferred the patient to the intensive care unit of a tertiary-care hospital in Karachi for additional testing and critical care. We sent a CSF sample for microscopic examination, chemical testing, and bacterial culture. The CSF sample was slightly turbid, and test results showed high levels of protein, 950 mg/dL (reference 15–40 mg/dL); glucose, 79.2 mg/dL (reference 50–80 mg/dL); erythrocytes, 52 cells/mm3 (reference 0 cells/mm3); and leukocytes, 162 cells/mm3 (reference 0–5 cells/mm3), with 60% segmented neutrophils. A wet mount of the CSF showed trophozoite forms of an ameba. We changed the patient’s treatment regimen to oral miltefosine (50 mg/6 h), intravenous amphotericin B (75 mg immediately, then 50 mg/24 h), oral rifampin (400 mg/12 h), intravenous fluconazole (400 mg/12 h), intravenous azithromycin (500 mg/24 h), intravenous sodium valproate (500 mg/8 h), and intravenous 20% mannitol (200 mL/8 h). The patient’s condition began to deteriorate, he had onset of seizures, and his Glasgow coma score dropped to 8/15. We placed him on mechanical ventilation 4 hours after transfer to intensive care.
On day 3, we began intrathecal amphotericin B (15 mg). The intrathecal catheter was accidently removed during nursing care, and we made the decision to discontinue the intrathecal amphotericin B. The clinical course was complicated by ventilator-associated Acinetobacter baumannii pneumonia that was successfully treated with intravenous and inhalational colistin. With combination therapy, the patient’s condition began to improve, and on day 8, he was successfully weaned off mechanical ventilation. He completed a 3-week course of therapy, and on day 28, he was discharged. The patient has since returned to his previous state of health without any neurologic deficit.
Naegleria fowleri (commonly referred to as the “brain-eating amoeba”), is a microscopic amoeba which is a single-celled living organism. It can cause a rare and devastating infection of the brain called primary amebic meningoencephalitis (PAM). The amoeba is commonly found in warm freshwater such as lakes, rivers, ponds and canals.
Infections can happen when contaminated water enters the body through the nose. Once the amoeba enters the nose, it travels to the brain where it causes PAM (which destroys brain tissue) and is usually fatal. Infections usually occur when it is hot for prolonged periods of time, which results in higher water temperatures and lower water levels.
Naegleria fowleri infections are rare. Most infections occur from exposure to contaminated recreational water. Cases due to the use of neti pots and the practice of ablution have been documented.
The practice of ablution is included in Yogic, Ayurvedic, and Islamic traditions. Within the Islamic faith, ritual nasal rinsing is included in a cleansing process called “wudu” or “ablution.” It is usually performed several times a day in preparation for prayer, according to the Centers for Disease Control and Prevention.
You cannot be infected with Naegleria fowleri by drinking contaminated water and the amoeba is not found in salt water.
Initial symptoms of PAM usually start within 1 to 7 days after infection. The initial symptoms may include headache, fever, nausea, or vomiting. Other symptoms can include stiff neck, confusion, loss of balance, seizures, and hallucinations. After the start of symptoms, the disease progresses rapidly.