- Volume 3, Issue 5, 2016

Helicobacter fennelliae is an enterohepatic Helicobacter species causing bacteraemia in immunocompromised hosts. Only a few cases of recurrent H. fennelliae bacteraemia have been reported in Japan and there are no guidelines regarding antimicrobial treatment for H. fennelliae infection.

H. fennelliae bacteraemia was observed in a patient receiving platinum-based chemotherapy for lung cancer. To prevent recurrence, the patient received antibiotic therapy with cefepime, amoxicillin and doxycycline for 6 weeks, which is similar to the therapy for Helicobacter cinaedi bacteraemia. Bacteraemia recurred despite the long-term antibiotic therapy. We hypothesized that the H. fennelliae bacteraemia originated from endogenous infection in the intestinal tract due to the long-term damage of the enteric mucosa by platinum-based drugs and performed selective digestive decontamination (SDD) with kanamycin. Bacteraemia did not recur after SDD.

Our observations indicate that clinicians should be aware of possible recurrent H. fennelliae bacteraemia, which could be effectively prevented by SDD with kanamycin.

Nutritionally variant streptococci (NVS) are an infrequent cause of human infection with Granulicatella elegans being the least encountered species in clinical specimens. The most common infection caused by NVS is infective endocarditis.

We report an unusual case of thoracic empyema due to G. elegans in a patient with pulmonary tuberculosis (TB) and human immunodeficiency virus infection. The patient responded favourably to drainage and penicillin.

This case illustrates that even though TB is responsible for the majority of pleural effusions in this setting, other rare opportunistic bacteria may cause infection in susceptible patients. Therefore, microbiological investigations should be performed in all patients presenting with pleural effusion.

Retrospective molecular identification of Leishmania parasites in two patients with visceral leishmaniasis (VL) previously treated in Serbia was carried out. DNA was isolated from unstained bone marrow smears (BMSs) kept for 11 and 8 years. Genus-specific real-time PCR was combined with conventional PCR and sequencing for detection and species identification.

In 2003, a 40-year-old Serbian male was admitted to the Clinical Centre of Serbia (CCS) with fever, sweating, fatigue and splenomegaly, which developed over a period of 7 weeks. He had frequently travelled around Europe. VL was confirmed by microscopy of Giemsa-stained BMS. Treatment by pentavalent antimonials was successfully completed. Two years later, the patient developed post-kala-azar dermal leishmaniasis. Treatment resulted in symptom resolution. Later on, Leishmania infantum was identified as the causative agent of the VL by sequencing of the ITS (internal transcribed spacer) region; mixed Leishmania spp. infection could not be excluded. In 2006, a 33-year-old female from Vojvodina, Serbia, with pre-existing diabetes mellitus and chronic meningoencephalitis and a history of frequent visits to the Montenegrin seacoast, was admitted to the CCS with fever, pancytopenia and moderate hepatosplenomegaly. A stained BMS revealed abundant Leishmania amastigotes. Indirect haemagglutination analysis was positive with a titre of 1 : 2048, and a rapid dipstick rK39 test was also positive. Treatment by liposomal amphotericin B was successful; however, shortly after, the patient developed neural infection and pneumonia and died. The causative agent was identified as L. infantum.

Molecular diagnosis of VL and species delineation using DNA from unstained BMSs stored for several years is possible.

Incidence rates of invasive Haemophilus influenzae serotype b disease have decreased significantly since the introduction of the Hib vaccine; however, the rates in indigenous populations remain disproportionately high, specifically in the paediatric population. Additionally, with the decline of type b invasive infections, there has been a rebound in the incidence of invasive infections caused by other strains of H. influenzae, particularly serotype a.

We present a paediatric case of septic arthritis caused by H. influenzae type a in a toddler that was fully resolved following antibiotic therapy. This report adds to other reports of septic arthritis in indigenous populations as shown through a review of recently documented H. influenzae type a septic arthritis cases.

Socio-economic risk factors for invasive H. influenzae type a disease, such as poverty, poor housing conditions, overcrowding, smoking and substance abuse during pregnancy, as well as the need for H. influenzae type a immunization of vulnerable populations, are discussed.

Gordonia spp. infections are uncommon. However, a few clinical cases have been reported in the literature, particularly those involving immunocompromised hosts. Advanced microbiology diagnosis techniques, such as matrix-assisted laser desorption ionization-time of flight MS (MALDI-TOF MS), have been recently introduced in clinical microbiology laboratories in order to improve microbial identification, resulting in better patient management.

Here, we present a new clinical case of persistent wound infection caused by Gordonia bronchialis in a 64-year-old woman after a mitral valve replacement, using two MALDI-TOF-based systems for identifying this micro-organism.

Both MALDI-TOF systems were able to identify Gordonia spp.; thus, providing a useful tool that overcomes the current limitations of phenotypic identification associated with this micro-organism. Although the technique validation deserves additional verification, our study provides guidance about MALDI-TOF as a fast and easy method for Gordonia spp. identification.

Globally, extra-intestinal pathogenic Escherichia coli are one of the predominant causative agents of bacteraemia.

This case report outlines a presentation of community-acquired pyelonephritis and secondary bloodstream infection in an 81-year-old man. Laboratory investigations revealed that the causative isolate was a multi-drug-resistant E. coli of a novel multi-locus sequence type. This sequence type (ST) was designated ST-458 and was most closely related to the globally prevalent ST-131 lineage.

This is the first report of a novel E. coli ST, ST-458, which caused pyelonephritis and bacteraemia.

Staphylococcus caprae is a rare cause of infective endocarditis. Here, we report a case involving the native mitral valve in the absence of an implantable cardiac electronic device.

A 76-year-old man presented with a 2 week history of confusion and pyrexia. His past medical history included an open reduction and internal fixation of a humeral fracture 17 years previously, which remained non-united despite further revision 4 years later. There was no history of immunocompromise or farm-animal contact. Two sets of blood culture bottles, more than 12 h apart, were positive for S. caprae. Trans-thoracic echocardiography revealed a 1×1.2 cm vegetation on the mitral valve, with moderate mitral regurgitation. Due to ongoing confusion, he had a magnetic resonance imaging brain scan, which showed a subacute small vessel infarct consistent with a thromboembolic source. A humeral SPECT-CT (single-photon emission computerized tomography-computerized tomography) scan showed no clear evidence of acute osteomyelitis. Surgical vegetectomy and mitral-valve repair were considered to reduce the risk of further systemic embolism and progressive valve infection. However, the potential risks of surgery to this patient led to a decision to pursue a cure with antibiotic therapy alone. He remained well 3 months after discharge, with repeat echocardiography demonstrating a reduction in the size of the vegetation (0.9 cm).

Management of this infection was challenging due to its rarity and its unclear progression, complicated by the dilemma surrounding surgical intervention in a patient with a complex medical background.

Streptococcus suis serotype 2 is an important swine pathogen and emerging zoonotic agent causing meningitis and septicemia/septic shock. Strains are usually virulent (Eurasia) or of intermediate/low virulence (North America). Very few data regarding human and swine isolates from South America are available.

Seventeen new human S. suis cases in Argentina (16 serotype 2 strains and a serotype 5 strain) are reported. Alongside, 14 isolates from pigs are analyzed: 12 from systemic disease, one from lungs and one from tonsils of a healthy animal. All human serotype 2 strains and most swine isolates are sequence type (ST) 1, as determined by multilocus sequence typing and present a mrp+/epf+/sly + genotype typical of virulent Eurasian ST1 strains. The remaining two strains (recovered from swine lungs and tonsils) are ST28 and possess a mrp+/epf − /sly− genotype typical of low virulence North American strains. Representative human ST1 strains as well as one swine ST28 strain were analyzed by whole-genome sequencing and compared with genomes from GenBank. ST1 strains clustered together with three strains from Vietnam and this cluster is close to another one composed of 11 strains from the United Kingdom.

Close contact with pigs/pork products, a good surveillance system, and the presence of potentially virulent Eurasian-like serotype 2 strains in Argentina may be an important factor contributing to the higher number of human cases observed. In fact, Argentina is now fifth among Western countries regarding the number of reported human cases after the Netherlands, France, the UK and Poland.

Invasive pneumococcal disease is an uncommon and notifiable disease in Singapore. It is often associated with significant morbidity and mortality. We report a rare case of invasive pneumococcal bacteraemia due to parotitis in a patient with systemic sclerosis and secondary Sjögren’s syndrome. We also present a retrospective review of Streptococcus pneumoniae bacteraemia cases in Singapore General Hospital from January 2011 to April 2016.

A 59-year-old Malay lady with a history of systemic sclerosis with secondary Sjögren’s syndrome presented with fever and left parotid gland swelling. Clinical examination revealed poor salivary pooling and left parotid swelling without fluctuance. Ultrasound of the left parotid gland confirmed acute parotitis without evidence of abscess or sialolithiasis. Blood cultures were positive for S. pneumoniae. She was diagnosed to have invasive pneumococcal bacteraemia secondary to acute parotitis, and treated with intravenous benzylpenicillin with clearance of bacteraemia after 3 days. Upon discharge, her antibiotics were changed to intravenous ceftriaxone to facilitate outpatient parenteral antibiotic therapy for another 2 weeks. She responded favourably to antibiotics at follow-up, with no complications from the bacteraemia. A review of the microbiological records of the Singapore General Hospital revealed 116 cases of pneumococcal bacteraemia, most (80.3 %) of which were due to pneumonia. None were due to parotitis.

S. pneumoniae parotitis and subsequent bacteraemia is rare. Prompt recognition of the disease and appropriate use of antibiotics are important. This case highlights that close communication between healthcare workers (microbiologist, rheumatologist and infectious disease specialist) is essential in ensuring good clinical outcomes in patients with a potentially fatal disease.