Last data update: Apr 29, 2024. (Total: 46658 publications since 2009)
Records 1-10 (of 10 Records) |
Query Trace: Ali IK[original query] |
---|
Use of a human indirect immunoflorescence antibody assay for Balamuthia mandrillaris in a group of captive northwest Bornean orangutans (Pongo pygmaeus pygmaeus)
Ferris RL , Ali IK , West G . J Zoo Wildl Med 2021 52 (1) 310-314 Granulomatous amoebic encephalitis caused by the free-living amoeba Balamuthia mandrillaris is a highly fatal disease that was first isolated from a mandrill (Mandrillus sphinx), and has since been diagnosed in several nonhuman primates including orangutans. Indirect immunofluorescence antibody (IFA) techniques for Balamuthia have been used in the fields of human medicine and epidemiology both for exposure assessment and screening of clinical patients for antemortem diagnosis. Stored serum samples from five captive Northwest Bornean orangutans (Pongo pygmaeus pygmaeus), including one who had died from B. mandrillaris infection, housed at a single facility were screened with a human IFA assay for B. mandrillaris. Only the single, clinically affected individual was seropositive, and the results suggest that the use of the available human B. mandrillaris IFA assay is a novel diagnostic option for detection of Balamuthia antibodies in this species. A validated screening serological test could be used in individuals exhibiting signs consistent with granulomatous amoebic encephalitis to facilitate earlier antemortem diagnosis of Balamuthia infection, which is critical if treatment is to be pursued. This pilot study presents the use of serological detection methods for B. mandrillaris screening in a nonhuman primate. Subsequent use of the B. mandrillaris IFA assay in the larger captive population should be pursued for validation of the test and to provide further information on seroprevalence and evaluation of risk factors for exposure to Balamuthia and subsequent development of disease. |
Primary amebic meningoencephalomyelitis caused by Naegleria fowleri in a south-central black rhinoceros (Diceros bicornis minor)
Yaw TJ , O'Neil P , Gary JM , Ali IK , Cowart JR , Wallace RS , Estep JS . J Am Vet Med Assoc 2019 255 (2) 219-223 CASE DESCRIPTION A 20-year-old female south-central black rhinoceros (Diceros bicornis minor) was evaluated because of an acute onset of CNS deficits. CLINICAL FINDINGS The rhinoceros had no history of illness. Clinical signs included acute lethargy, ataxia, and decreased appetite. Hematologic abnormalities included leukocytosis with neutrophilia and a profound left shift. Results of serum biochemical analysis revealed hypophosphatemia but no other abnormalities. Results of a quantitative PCR assay for West Nile virus and an assay for anti-Neosporum caninum antibodies in serum were negative; the patient was seropositive for multiple Leptospira serovars. TREATMENT AND OUTCOME Antimicrobials and anti-inflammatory agents were administered, but the condition of the rhinoceros worsened overnight; despite treatment with additional anti-inflammatory and antimicrobial agents, IV fluids, and thiamine, it became obtunded and died of respiratory arrest </= 24 hours later. Necropsy revealed severe, diffuse, suppurative, and histiocytic meningo-encephalomyelitis involving the cerebrum, cerebellum, and spinal cord. Amebic trophozoites were observed on histologic examination of affected tissue. Infection with Naegleria fowleri was confirmed by results of immuno-histochemical analysis and a multiplex real-time PCR assay. CLINICAL RELEVANCE Findings suggested that south-central black rhinoceros are susceptible to the free-living ameba N fowleri. Ameba-induced meningoencephalomyelitis should be considered as a differential diagnosis for rhinoceros that have an acute onset of neurologic signs. Diagnosis of N fowleri infection in an animal has a profound public health impact because of potential human exposure from the environment and the high fatality rate in people with N fowleri infection. |
Case Report: Cervicovaginal co-colonization with Entamoeba gingivalis and Entamoeba polecki in association with an intrauterine device
Bradbury RS , Roy S , Ali IK , Morrison JR , Waldner D , Hebbeln K , Aldous W , Jepson R , Delavan HR , Ndubuisi M , Bishop HS . Am J Trop Med Hyg 2018 100 (2) 311-313 Amoebic trophozoites were identified in the cervicovaginal smear of a U.S. patient without travel history at the time of intrauterine device (IUD) removal. Subsequent morphologic analysis and DNA sequencing identified a mixed cervicovaginal colonization of the female genital tract with both Entamoeba gingivalis and Entamoeba polecki in association with Actinomyces species bacteria. This highlights to the potential for colonization of the genital tract with E. gingivalis, particularly in association with IUD placement, and represents the first report of E. polecki in this context. |
The epidemiology and clinical features of Balamuthia mandrillaris disease in the United States, 1974 - 2016
Cope JR , Landa J , Nethercut H , Collier SA , Glaser C , Moser M , Puttagunta R , Yoder JS , Ali IK , Roy SL . Clin Infect Dis 2018 68 (11) 1815-1822 Background: Balamuthia mandrillaris is a free-living ameba that causes rare, nearly always fatal disease in humans and animals worldwide. B. mandrillaris has been isolated from soil, dust, and water. Initial entry of Balamuthia into the body is likely via the skin or lungs. To date, only individual case reports and small case series have been published. Methods: The Centers for Disease Control and Prevention (CDC) maintains a free-living ameba (FLA) registry and laboratory. To be entered into the registry, a Balamuthia case must be laboratory-confirmed. Several sources were used to complete entries in the registry, including case report forms, CDC laboratory results, published case reports, and media information. SAS(c) version 9.3 software was used to calculate descriptive statistics and frequencies. Results: We identified 109 case reports of Balamuthia disease between 1974 and 2016. Most (99%) had encephalitis. The median age was 36 years (range 4 months to 91 years). Males accounted for 68% of the case patients. California had the highest number of case reports followed by Texas and Arizona. Hispanics constituted 55% for those with documented ethnicity. Exposure to soil was commonly reported. Among those with a known outcome, 90% of patients died. Conclusions: Balamuthia disease in the United States is characterized by a highly fatal encephalitis that affects patients of all ages. Hispanics were disproportionately affected. The southwest region of the U.S. reported the most cases. Clinician awareness of Balamuthia as a cause of encephalitis might lead to earlier diagnosis and initiation of treatment, resulting in better outcomes. |
Acanthamoeba granulomatous amoebic encephalitis after pediatric hematopoietic stem cell transplant
Coven SL , Song E , Steward S , Pierson CR , Cope JR , Ali IK , Ardura MI , Hall MW , Chung MG , Bajwa RPS . Pediatr Transplant 2017 21 (8) Acanthamoeba encephalitis is a rare, often fatal condition, particularly after HSCT, with 9 reported cases to date in the world literature. Our case was originally diagnosed with ALL at age 3 years, and after several relapses underwent HSCT at age 9 years. At 17 years of age, he was diagnosed with secondary AML for which he underwent a second allogeneic HSCT. He presented with acute-onset worsening neurological deficits on day +226 after the second transplant and a post-mortem diagnosis of Acanthamoeba encephalitis was established, with the aid of the CDC. |
Biology and pathogenesis of Naegleria fowleri
Siddiqui R , Ali IK , Cope JR , Khan NA . Acta Trop 2016 164 375-394 Naegleria fowleri is a protist pathogen that can cause lethal brain infection. Despite decades of research, the mortality rate related with primary amoebic meningoencephalitis owing to N. fowleri remains more than 90%. The amoebae pass through the nose to enter the central nervous system killing the host within days, making it one of the deadliest opportunistic parasites. Accordingly, we present an up to date review of the biology and pathogenesis of N. fowleri and discuss needs for future research against this fatal infection. |
Primary Amebic Meningoencephalitis: What Have We Learned in the Last 5 Years?
Cope JR , Ali IK . Curr Infect Dis Rep 2016 18 (10) 31 Primary amebic meningoencephalitis (PAM) is a devastating infection of the brain caused by the thermophilic free-living ameba, Naegleria fowleri. Infection can occur when water containing the ameba enters the body through the nose, usually during recreational water activities such as swimming or diving. Historically, in the USA, cases were mostly reported from the warmer southern-tier states. In the last 5 years, several notable changes have been documented in PAM epidemiology including a northward expansion of infections and new types of water exposures. The recent reports of two PAM survivors provide hope for improved outcomes with early diagnosis and aggressive treatment. Advanced molecular laboratory tools such as genome sequencing might provide more insight into the pathogenicity of N. fowleri. Clinicians treating patients with meningitis and warm freshwater exposure are encouraged to consider PAM in their differential diagnoses. |
Diagnosing Balamuthia mandrillaris Encephalitis With Metagenomic Deep Sequencing.
Wilson MR , Shanbhag NM , Reid MJ , Singhal NS , Gelfand JM , Sample HA , Benkli B , O'Donovan B , Ali IK , Keating MK , Dunnebacke TH , Wood MD , Bollen A , DeRisi JL . Ann Neurol 2015 78 (5) 722-30 OBJECTIVE: Identification of a particular cause of meningoencephalitis can be challenging due to the myriad bacteria, viruses, fungi, and parasites that can produce overlapping clinical phenotypes, frequently delaying diagnosis and therapy. Metagenomic deep sequencing (MDS) approaches to infectious disease diagnostics are known for their ability to identify unusual or novel viruses and thus are well suited for investigating possible etiologies of meningoencephalitis. METHODS: We present the case of a 74 year-old woman with endophthalmitis followed by meningoencephalitis. MDS of her cerebrospinal fluid (CSF) was performed to identify an infectious agent. RESULTS: Sequences aligning to Balamuthia mandrillaris ribosomal RNA genes were identified in the CSF via MDS. Polymerase chain reaction (PCR) subsequently confirmed the presence of B. mandrillaris in CSF, brain tissue, and vitreous fluid from the patient's infected eye. B. mandrillaris serology and immunohistochemistry for free-living amoebas on the brain biopsy tissue were positive. INTERPRETATION: The diagnosis was made using MDS after the patient had been hospitalized for several weeks and subjected to costly and invasive testing. MDS a powerful diagnostic tool with the potential for rapid and unbiased pathogen identification leading to early therapeutic targeting. |
Re-evaluation of an Acanthamoeba Molecular Diagnostic Algorithm following an Atypical Case of Amoebic Keratitis.
Lau R , Cunanan M , Jackson J , Ali IK , Chong-Kit A , Gasgas J , Tian J , Ralevski F , Boggild AK . J Clin Microbiol 2015 BACKGROUND: Amoebic keratitis (AK) is a potentially blinding infection, the prompt diagnosis of which is essential to limiting ocular morbidity. We undertook a quality improvement initiative around the molecular detection of Acanthamoebae in our laboratory due to an unusual case of discordance. METHODS: Nine ATCC strains of Acanthamoeba and 40 delinked, biobanked surplus corneal scrapings were retrieved and analyzed for the presence of Acanthamoebae by 4 separate real time PCR assays. The assay used by the Free Living and Intestinal Amebas laboratory of the CDC was considered the reference standard, and performance characteristics of each individual assay, and pairs of assays were calculated. Outcome measures were sensitivity, specificity, and positive predictive value (PPV) and negative (NPV) predictive value. RESULTS: Of 49 included specimens, 14 (28.6%) were positive by the gold standard assay, and 35 (71.4%) were negative. Sensitivity of the individual test assays ranged from 64.3% to 92.9% compared to the gold standard, while specificity ranged from 88.6% to 91.4%. PPV and NPV ranged from 69.2% to 78.6%, and 86.1% to 96.9%, respectively. Combinations of assay pairs led to improved performance with sensitivities ranging from 92.9% to 100%, and specificity from 97.1% to 100%. ATCC and clinical strains of Acanthamoeba that failed detection by certain individual assays included A. castellani, A. culbertsoni, and A. lenticulata. In 3 clinical specimens, false negativity of the gold standard assay could not be excluded. CONCLUSIONS: Molecular diagnostic approaches, especially combinations of both highly sensitive and specific assays, offer a reasonably performing, operator independent, and rapid strategy for the detection of Acanthamoebae from clinical specimens, and are likely more practical than either culture or direct microscopic detection. |
Intestinal Amebae.
Ali IK . Clin Lab Med 2015 35 (2) 393-422 Among the Entamoeba species that infect humans, Entamoeba histolytica causes diseases, Entamoeba dispar is a harmless commensal, Entamoeba moshkovskii seems to be a pathogen, and the pathogenicity of Entamoeba bangladeshi remains to be investigated. Species-specific detection needed for treatment decisions and for understanding the epidemiology and pathogenicity of these amebae. Antigen-based detection methods are needed for E dispar, E moshkovskii, and E bangladeshi; and molecular diagnostic test capable of detecting E histolytica, E dispar, E moshkovskii, and E bangladeshi simultaneously in clinical samples. Next-generation sequencing of DNA from stool is needed to identify novel species of Entamoeba. |
- Page last reviewed:Feb 1, 2024
- Page last updated:Apr 29, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure