RESUMEN
We describe a classic case of nasal rhinosporidiosis in a woman who resided in Johannesburg, South Africa, but originated from a rural area in Eastern Cape Province. We confirmed histologic diagnosis using PCR testing and compared details with those from records on 17 other cases from South Africa.
Asunto(s)
Rinosporidiosis , Femenino , Humanos , Sudáfrica/epidemiología , Rinosporidiosis/diagnóstico , NarizRESUMEN
Tanapox is a rarely diagnosed zoonosis known to be endemic to equatorial Africa. All previously reported human cases were acquired within 10° north or south of the Equator, most recently 19 years ago. We describe a human case of tanapox in South Africa (24° south of the Equator). Expanded surveillance for this pathogen is warranted.
Asunto(s)
Infecciones por Poxviridae , Yatapoxvirus , Animales , Humanos , Sudáfrica/epidemiología , Zoonosis , Infecciones por Poxviridae/diagnósticoRESUMEN
We reevaluated 20 cases of blastomycosis diagnosed in South Africa between 1967 and 2014, with Blastomyces dermatitidis considered to be the etiological agent, in light of newly described species and the use of more advanced technologies. In addition to histopathological and/or culture-based methods, all 20 isolates were phenotypically and genotypically characterized, including multilocus typing of five genes and whole-genome sequencing. Antifungal susceptibility testing was performed as outlined by Clinical and Laboratory Standards Institute documents M27-A3 and M38-A2. We merged laboratory and corresponding clinical case data, where available. Morphological characteristics and phylogenetic analyses of five-gene and whole-genome sequences revealed two groups, both of which were closely related to but distinct from B. dermatitidis, Blastomyces gilchristii, and Blastomyces parvus The first group (n = 12) corresponded to the recently described species Blastomyces percursus, and the other (n = 8) is described here as Blastomyces emzantsi sp. nov. Both species exhibited incomplete conversion to the yeast phase at 37°C and were heterothallic for mating types. All eight B. emzantsi isolates belonged to the α mating type. Whole-genome sequencing confirmed distinct species identities as well as the absence of a full orthologue of the BAD-1 gene. Extrapulmonary (skin or bone) disease, probably resulting from hematogenous spread from a primary lung infection, was more common than pulmonary disease alone. Voriconazole, posaconazole, itraconazole, amphotericin B, and micafungin had the most potent in vitro activity. Over the 5 decades, South African cases of blastomycosis were caused by species that are distinct from B. dermatitidis Increasing clinical awareness and access to simple rapid diagnostics may improve the diagnosis of blastomycosis in resource-limited countries.
Asunto(s)
Blastomyces , Blastomicosis , Blastomyces/genética , Blastomicosis/diagnóstico , Blastomicosis/etiología , Humanos , Masculino , Filogenia , SudáfricaRESUMEN
In 2018, the family Arenaviridae was expanded by inclusion of 1 new genus and 5 novel species. At the same time, the recently established order Bunyavirales was expanded by 3 species. This article presents the updated taxonomy of the family Arenaviridae and the order Bunyavirales as now accepted by the International Committee on Taxonomy of Viruses (ICTV) and summarizes additional taxonomic proposals that may affect the order in the near future.
Asunto(s)
Arenaviridae/clasificación , Animales , Arenaviridae/genética , Arenaviridae/aislamiento & purificación , Infecciones por Arenaviridae/veterinaria , Infecciones por Arenaviridae/virología , Humanos , FilogeniaRESUMEN
The Bunyaviridae family comprises viruses causing diseases of public and veterinary health importance, including viral haemorrhagic and arboviral fevers. We report the isolation, identification and genome characterization of a novel orthobunyavirus, named Wolkberg virus (WBV), from wingless bat fly ectoparasites (Eucampsipoda africana) of Egyptian fruit bats (Rousettus aegyptiacus) in South Africa. Complete genome sequence data of WBV suggests it is most closely related to two bat viruses (Mojuí dos Campos and Kaeng Khoi viruses) and an arbovirus (Nyando virus) previously shown to infect humans. WBV replicates to high titres in VeroE6 and C6-36 cells, characteristic of mosquito-borne arboviruses. These findings expand our knowledge of the diversity of orthobunyaviruses and their insect vector host range.
Asunto(s)
Quirópteros/parasitología , Dípteros/virología , Orthobunyavirus/clasificación , Orthobunyavirus/aislamiento & purificación , Animales , Línea Celular , Análisis por Conglomerados , Genoma Viral , Microscopía Electrónica de Transmisión , Orthobunyavirus/genética , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia , Sudáfrica , Virión/ultraestructura , Cultivo de VirusRESUMEN
BACKGROUND: The meningococcal capsule is an important virulence determinant. Unencapsulated meningococci lacking capsule biosynthesis genes and containing the capsule null locus (cnl) are predominantly non-pathogenic. Rare cases of invasive meningococcal disease caused by cnl isolates belonging to sequence types (ST) and clonal complexes (cc) ST-845 (cc845), ST-198 (cc198), ST-192 (cc192) and ST-53 (cc53) have been documented. The clinical significance of these isolates however remains unclear. We identified four invasive cnl meningococci through laboratory-based surveillance in South Africa from 2003 through 2013, which we aimed to characterize using whole genome data. RESULTS: One isolate [NG: P1.7-2,30: F1-2: ST-53 (cc53)] contained cnl allele 12, and caused empyema in an adult male with bronchiectasis from tuberculosis, diabetes mellitus and a smoking history. Three isolates were NG: P1.18-11,42-2: FΔ: ST-192 (cc192) and contained cnl allele 2. One patient was an adolescent male with meningitis. The remaining two isolates were from recurrent disease episodes (8 months apart) in a male child with deficiency of the sixth complement component, and with the exception of two single nucleotide polymorphisms, contained identical core genomes. The ST-53 (cc53) isolate possessed alleles for NHBA peptide 191 and fHbp variant 2; whilst the ST-192 (cc192) isolates contained NHBA peptide 704 and fHbp variant 3. All four isolates lacked nadA. Comparison of the South African genomes to 61 additional cnl genomes on the PubMLST Neisseria database ( http://pubmlst.org/neisseria/ ), determined that most putative virulence genes could be found in both invasive and carriage phenotypes. CONCLUSIONS: Although rare, invasive disease by cnl meningococci may be associated with host immunodeficiency and such patients may benefit from protein-based meningococcal vaccines.
Asunto(s)
Cápsulas Bacterianas/genética , Genes Bacterianos/genética , Infecciones Meningocócicas/microbiología , Neisseria meningitidis/genética , Adhesinas Bacterianas/genética , Adolescente , Alelos , Antígenos Bacterianos/genética , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/genética , Secuencia de Bases , Bronquiectasia/complicaciones , Proteínas Portadoras/genética , Niño , Preescolar , Complicaciones de la Diabetes , Diabetes Mellitus , Empiema/microbiología , Sitios Genéticos , Marcadores Genéticos/genética , Humanos , Masculino , Meningitis Meningocócica/epidemiología , Infecciones Meningocócicas/epidemiología , Vacunas Meningococicas/inmunología , Persona de Mediana Edad , Anotación de Secuencia Molecular , Neisseria meningitidis/citología , Neisseria meningitidis/aislamiento & purificación , Neisseria meningitidis/patogenicidad , Fenotipo , Filogenia , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , Fumar , Sudáfrica/epidemiología , Tuberculosis/complicaciones , Virulencia/genética , Adulto JovenRESUMEN
BACKGROUND: More than 94 serotypes of Streptococcus pneumoniae have been described to date, however the majority of disease is caused by approximately 20 serotypes. Some pneumococci do not react with commercially available antisera used for serotyping and are thus regarded as non-serotypeable (NT). These pneumococci are commonly isolated during carriage studies and very rarely cause invasive disease. Colonization may occur with more than one serotype however disease with more than one serotype is rarely detected. Thus there are limited data describing cases of pneumococcal disease caused by more than one isolate. RESULTS: In two cases of invasive pneumococcal disease in South Africa, a non-serotypeable and a serotypeable isolate were co-detected during routine serotyping. A serotype 1 and 18C isolate were each co-detected with a non-serotypeable isolate in 2009 (case A) and 2010 (case B), from cerebrospinal fluid and blood, respectively. Both patients were 10-14 years old. For case A, the serotypeable isolate could not be obtained due to low representation in the mixed culture. Using electron microscopy we confirmed lack of capsule for the non-serotypeable isolates. Comparison of the case A non-serotypeable isolate with a serotype 1 genome revealed only the presence of the rhamnose biosynthesis genes (rmlA, B, C and D) in the capsular locus, all other capsular genes were absent. Nonetheless it had a multilocus sequence type (ST) associated with serotype 1 (ST217 and ribosomal ST3462) and its core genome clustered with other ST217 isolates. The case B non-serotypeable isolate had all serotype 18C capsular genes except for variation in the wchA and wze genes, compared to the 18C isolate. Both case B isolates were ST9817 and their core genomes were identical. CONCLUSIONS: The ability of pneumococci to alter capsule production is a potential vaccine escape mechanism and therefore non-serotypeable pneumococci should be monitored as such organisms may increase under vaccine pressure.
Asunto(s)
Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/aislamiento & purificación , Adolescente , Niño , Humanos , Masculino , Infecciones Neumocócicas/diagnóstico , Serotipificación , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/genéticaRESUMEN
Disulfiram (DSF), used since the 1950s in the treatment of alcoholism, is reductively activated to diethyldithiocarbamate and both compounds are thiol-reactive and readily complex copper. More recently DSF and copper-DSF (Cu-DSF) have been found to exhibit potent anticancer activity. We have previously shown that the anti-diabetic drug metformin is anti-proliferative and induces an intracellular reducing environment in oesophageal squamous cell carcinoma (OSCC) cell lines. Based on these observations, we investigated the effects of Cu-DSF and DSF, with and without metformin, in this present study. We found that Cu-DSF and DSF caused considerable cytotoxicity across a panel of OSCC cells, and metformin significantly enhanced the effects of DSF. Elevated copper transport contributes to DSF and metformin-DSF-induced cytotoxicity since the cell-impermeable copper chelator, bathocuproinedisulfonic acid, partially reversed the cytotoxic effects of these drugs, and interestingly, metformin-treated OSCC cells contained higher intracellular copper levels. Furthermore, DSF may target cancer cells preferentially due to their high dependence on protein degradation/turnover pathways, and we found that metformin further enhances the role of DSF as a proteasome inhibitor. We hypothesized that the lysosome could be an additional, novel, target of DSF. Indeed, this acid-labile compound decreased lysosomal acidification, and DSF-metformin co-treatment interfered with the progression of autophagy in these cells. In summary, this is the first such report identifying the lysosome as a target of DSF and based on the considerable cytotoxic effects of DSF either alone or in the presence of metformin, in vitro, and we propose these as novel potential chemotherapeutic approaches for OSCC.
Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Cobre/administración & dosificación , Disulfiram/administración & dosificación , Neoplasias Esofágicas/tratamiento farmacológico , Metformina/administración & dosificación , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Sinergismo Farmacológico , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago , Humanos , Complejo de la Endopetidasa Proteasomal/administración & dosificación , Proteolisis/efectos de los fármacosRESUMEN
Microsporidia are an emerging group of pathogens associated with life-threatening opportunistic infections in immunocompromised hosts, particularly human immunodeficiency virus (HIV)-infected individuals. There have, however, been recent reports of infection in adult solid organ transplant recipients. We report two cases in children, to our knowledge the first in the paediatric literature. Two 13-yr-old, HIV-seronegative females received deceased donor renal transplants from the same donor. Both patients suffered acute cell-mediated rejection and CMV infection reactivation, managed with intensified immunosuppression and ganciclovir. Pyrexia of unknown origin and intermittent diarrhea in both prompted extensive investigations. In both patients, numerous spores of a microsporidial species were demonstrated in renal tissue on biopsy and in the urine, using modified trichrome and quick-hot Gram-chromotrope staining. Electron microscopy and PCR confirmed Encephalitozoon cuniculi infections. Both patients were successfully treated with 400 mg twice daily of albendazole, with sustained clinical improvement. We recommend that microsporidiosis be considered in the differential diagnosis of pyrexia of unknown origin in severely immunocompromised pediatric solid organ transplant recipients, particularly when associated with diarrhea.
Asunto(s)
Trasplante de Riñón/efectos adversos , Microsporidiosis/etiología , Adolescente , Albendazol/uso terapéutico , Infecciones por Citomegalovirus , Diarrea/etiología , Encephalitozoon cuniculi , Femenino , Fiebre , Ganciclovir/uso terapéutico , Rechazo de Injerto , Humanos , Inmunosupresores/uso terapéutico , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/cirugía , Síndrome Nefrótico/complicaciones , Síndrome Nefrótico/cirugía , Complicaciones Posoperatorias , Insuficiencia Renal , SudáfricaRESUMEN
Introduction: International guidelines recommend a multi-faceted approach for successful diagnoses of primary ciliary dyskinesia (PCD). In the absence of a gold standard test, a combination of genetic testing/microscopic analysis of structure and function/nasal nitric oxide measurement is used. In resource-limited settings, often none of the above tests are available, and in South Africa, only transmission electron microscopy (TEM) is available in central anatomical pathology departments. The aim of this study was to describe the clinical and ultrastructural findings of suspected PCD cases managed by pediatric pulmonologists at a tertiary-level state funded hospital in Johannesburg. Methods: Nasal brushings were taken from 14 children with chronic respiratory symptoms in keeping with a PCD phenotype. Ultrastructural analysis in accordance with the international consensus guidelines for TEM-PCD diagnostic reporting was undertaken. Results: TEM observations confirmed 43% (6) of the clinically-suspected cases (hallmark ultrastructural defects in the dynein arms of the outer doublets), whilst 57% (8) required another PCD testing modality to support ultrastructural observations. Of these, 25% (2) had neither ultrastructural defects nor did they present with bronchiectasis. Of the remaining cases, 83% (5) had very few ciliated cells (all of which were sparsely ciliated), together with goblet cell hyperplasia. There was the apparent absence of ciliary rootlets in 17% (1) case. Discussion: In resource-limited settings in which TEM is the only available testing modality, confirmatory and probable diagnoses of PCD can be made to facilitate early initiation of treatment of children with chronic respiratory symptoms.
RESUMEN
INTRODUCTION: Herpes simplex virus has been reported in the literature to commonly complicate burn wounds. However, there is paucity of such data in the South African setting. CASE PRESENTATION: Eight paediatric burns patients with ages ranging between 10 months and 5 years presented with a febrile maculopapular rash illness in a paediatric ward of a large South African tertiary hospital. The rash became vesicular in three cases, involving the limbs and face. Varicella was suspected. MANAGEMENT AND OUTCOME: Medical records of suspected cases were reviewed. Blood, vesicular fluid and scab samples were collected. Electron microscopy of vesicular fluid revealed herpes virus particles. Laboratory testing confirmed herpes simplex virus type 1. CONCLUSION: Herpes simplex virus type 1 infection can present atypically in burns patients.
RESUMEN
Two cases of cryptococcal meningitis went undetected by a cryptococcal antigen (CrAg) lateral flow assay on blood in a reflex CrAg screen-and-treat programme in South Africa, although Cryptococcus neoformans was identified by culturing the cerebrospinal fluid specimens. Further investigations into these discordant diagnostic results included multilocus sequence typing (which showed no mutations in the CAP59 gene) and transmission electron microscopy using a capsule-staining protocol (which revealed a >50% reduction in capsular material in both cases, relative to a control culture). A multi-disciplinary approach for resolving discordant diagnostic test results is recommended.
RESUMEN
Recently a number of novel adenoviruses have been isolated from diverse bat species and from diverse geographical locations. We describe the isolation of a novel adenovirus (Family Adenoviridae, genus Mastadenovirus) from a pool of liver and spleen tissue of an apparently healthy wild-caught Egyptian fruit bat (Rousettus aegyptiacus) in South Africa. Genetically the virus is most closely related to four mastadenoviruses recently isolated in China, from Miniopterus schreibersi and Rousettus leschenaultii bats, which are highly divergent from previously identified bat adenoviruses. The length of the Rousettus aegyptiacus adenovirus-3085 (RaegAdV-3085) genome, at 29,342 bp is similar to its closest relatives, and contains 27 open reading frames. The RaegAdV-3085 genome has a low G + C content (36.4%) relative to other viruses in the genus (between 43.6 and 63.9%) but similar to its closest relatives. The inverted terminal repeat (ITR) of RaegAdV-3085 is only 40 bp compared to between 61 and 178 bp of its closest relatives. The discovery of RaegAdV-3085 expands the diversity of known adenoviruses in bats and might represent a member of a new mastadenovirus species in bats.
Asunto(s)
Adenoviridae/clasificación , Adenoviridae/aislamiento & purificación , Quirópteros/virología , Adenoviridae/genética , Animales , China , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Hígado/virología , Filogenia , Sudáfrica , Bazo/virología , Secuenciación Completa del GenomaRESUMEN
We report on the isolation of a novel fusogenic orthoreovirus from bat flies (Eucampsipoda africana) associated with Egyptian fruit bats (Rousettus aegyptiacus) collected in South Africa. Complete sequences of the ten dsRNA genome segments of the virus, tentatively named Mahlapitsi virus (MAHLV), were determined. Phylogenetic analysis places this virus into a distinct clade with Baboon orthoreovirus, Bush viper reovirus and the bat-associated Broome virus. All genome segments of MAHLV contain a 5' terminal sequence (5'-GGUCA) that is unique to all currently described viruses of the genus. The smallest genome segment is bicistronic encoding for a 14 kDa protein similar to p14 membrane fusion protein of Bush viper reovirus and an 18 kDa protein similar to p16 non-structural protein of Baboon orthoreovirus. This is the first report on isolation of an orthoreovirus from an arthropod host associated with bats, and phylogenetic and sequence data suggests that MAHLV constitutes a new species within the Orthoreovirus genus.
Asunto(s)
Dípteros/virología , Genoma Viral , Orthoreovirus/clasificación , Orthoreovirus/aislamiento & purificación , ARN Viral/genética , Análisis de Secuencia de ADN , Animales , Quirópteros/parasitología , Análisis por Conglomerados , Microscopía Electrónica de Transmisión , Peso Molecular , Orthoreovirus/ultraestructura , Filogenia , Homología de Secuencia , Homología de Secuencia de Aminoácido , Sudáfrica , Proteínas Virales/química , Proteínas Virales/genética , Virión/ultraestructuraRESUMEN
The Egyptian fruit bat, Rousettus aegyptiacus, is currently regarded as a potential reservoir host for Marburg virus (MARV). However, the modes of transmission, the level of viral replication, tissue tropism and viral shedding pattern remains to be described. Captive-bred R. aegyptiacus, including adult males, females and pups were exposed to MARV by different inoculation routes. Blood, tissues, feces and urine from 9 bats inoculated by combination of nasal and oral routes were all negative for the virus and ELISA IgG antibody could not be demonstrated for up to 21 days post inoculation (p.i.). In 21 bats inoculated by a combination of intraperitoneal/subcutaneous route, viremia and the presence of MARV in different tissues was detected on days 2-9 p.i., and IgG antibody on days 9-21 p.i. In 3 bats inoculated subcutaneously, viremia was detected on days 5 and 8 (termination of experiment), with virus isolation from different organs. MARV could not be detected in urine, feces or oral swabs in any of the 3 experimental groups. However, it was detected in tissues which might contribute to horizontal or vertical transmission, e.g. lung, intestines, kidney, bladder, salivary glands, and female reproductive tract. Viremia lasting at least 5 days could also facilitate MARV mechanical transmission by blood sucking arthropods and infections of susceptible vertebrate hosts by direct contact with infected blood. All bats were clinically normal and no gross pathology was identified on post mortem examination. This work confirms the susceptibility of R. aegyptiacus to infection with MARV irrespective of sex and age and contributes to establishing a bat-filovirus experimental model. Further studies are required to uncover the mode of MARV transmission, and to investigate the putative role of R. aegyptiacus as a reservoir host.
Asunto(s)
Quirópteros/inmunología , Quirópteros/virología , Marburgvirus/inmunología , Animales , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Chlorocebus aethiops , Femenino , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Masculino , Marburgvirus/genética , Marburgvirus/aislamiento & purificación , ARN Viral/genética , Células Vero , Carga ViralRESUMEN
Lactobacillus jensenii, Lactobacillus crispatus, Lactobacillus iners, Lactobacillus gasseri and Lactobacillus vaginalis were identified by 16S rRNA gene sequencing as the predominant culturable vaginal Lactobacillus species in a group of South African women, comprising 24, 22, 10, 10 and 9â%, respectively. A significant effect of vaginal discharge syndrome (VDS) and bacterial vaginosis (BV) on the distribution of predominant Lactobacillus species was observed. Whilst L. crispatus isolates were almost equally distributed between individuals with and without VDS and were not significantly reduced in women with BV versus normal microflora, L. jensenii isolates were significantly reduced in women with VDS (P=0.022) and reduced in women with BV versus normal microflora (P=0.053). Unlike L. crispatus, L. jensenii isolates were also significantly reduced in women with BV-associated VDS versus women without VDS and with normal microflora (P=0.051). In addition, lysogeny was commonly observed for L. crispatus, with 77â% of isolates yielding phage particles with contractile and non-contractile tails. Only 29â% of L. jensenii isolates yielded phage particles, and these were visible as tailless or podo-like particles.