CD4/CD8 Ratio and the Risk of Kaposi Sarcoma or Non-Hodgkin Lymphoma in the Context of Efficiently Treated Human Immunodeficiency Virus (HIV) Infection: A Collaborative Analysis of 20 European Cohort Studies.

BACKGROUND: A persistently low CD4/CD8 ratio has been reported to inversely correlate with the risk of non-AIDS defining cancer in people living with human immunodeficiency virus (HIV; PLWH) efficiently treated by combination antiretroviral therapy (cART). We evaluated the impact of the CD4/CD8 ratio on the risk of Kaposi sarcoma (KS) or non-Hodgkin lymphoma (NHL), still among the most frequent cancers in treated PLWH. METHODS: PLWH from the Collaboration of Observational HIV Epidemiological Research Europe (COHERE) were included if they achieved virological control (viral load ≤ 500 copies/mL) within 9 months following cART and without previous KS/LNH diagnosis. Cox models were used to identify factors associated with KS or NHL risk, in all participants and those with CD4 ≥ 500/mm3 at virological control. We analyzed the CD4/CD8 ratio, CD4 count and CD8 count as time-dependent variables, using spline transformations. RESULTS: We included 56 708 PLWH, enrolled between 2000 and 2014. At virological control, the median (interquartile range [IQR]) CD4 count, CD8 count, and CD4/CD8 ratio were 414 (296-552)/mm3, 936 (670-1304)/mm3, and 0.43 (0.28-0.65), respectively. Overall, 221 KS and 187 NHL were diagnosed 9 (2-37) and 18 (7-42) months after virological control. Low CD4/CD8 ratios were associated with KS risk (hazard ratio [HR] = 2.02 [95% confidence interval {CI } = 1.23-3.31]) when comparing CD4/CD8 = 0.3 to CD4/CD8 = 1) but not with NHL risk. High CD8 counts were associated with higher NHL risk (HR = 3.14 [95% CI = 1.58-6.22]) when comparing CD8 = 3000/mm3 to CD8 = 1000/mm3). Similar results with increased associations were found in PLWH with CD4 ≥ 500/mm3 at virological control (HR = 3.27 [95% CI = 1.60-6.56] for KS; HR = 5.28 [95% CI = 2.17-12.83] for NHL). CONCLUSIONS: Low CD4/CD8 ratios and high CD8 counts despite effective cART were associated with increased KS/NHL risks respectively, especially when CD4 ≥ 500/mm3.

Point-prevalence survey of healthcare facility-onset healthcare-associated Clostridium difficile infection in Greek hospitals outside the intensive care unit: The C. DEFINE study.

BACKGROUND: The correlation of Clostridium difficile infection (CDI) with in-hospital morbidity is important in hospital settings where broad-spectrum antimicrobial agents are routinely used, such as in Greece. The C. DEFINE study aimed to assess point-prevalence of CDI in Greece during two study periods in 2013. METHODS: There were two study periods consisting of a single day in March and another in October 2013. Stool samples from all patients hospitalized outside the ICU aged ≥18 years old with diarrhea on each day in 21 and 25 hospitals, respectively, were tested for CDI. Samples were tested for the presence of glutamate dehydrogenase antigen (GDH) and toxins A/B of C. difficile; samples positive for GDH and negative for toxins were further tested by culture and PCR for the presence of toxin genes. An analysis was performed to identify potential risk factors for CDI among patients with diarrhea. RESULTS: 5,536 and 6,523 patients were screened during the first and second study periods, respectively. The respective point-prevalence of CDI in all patients was 5.6 and 3.9 per 10,000 patient bed-days whereas the proportion of CDI among patients with diarrhea was 17% and 14.3%. Logistic regression analysis revealed that solid tumor malignancy [odds ratio (OR) 2.69, 95% confidence interval (CI): 1.18-6.15, p = 0.019] and antimicrobial administration (OR 3.61, 95% CI: 1.03-12.76, p = 0.045) were independent risk factors for CDI development. Charlson's Comorbidity Index (CCI) >6 was also found as a risk factor of marginal statistical significance (OR 2.24, 95% CI: 0.98-5.10). Median time to CDI from hospital admission was shorter with the presence of solid tumor malignancy (3 vs 5 days; p = 0.002) and of CCI >6 (4 vs 6 days, p = 0.009). CONCLUSIONS: The point-prevalence of CDI in Greek hospitals was consistent among cases of diarrhea over a 6-month period. Major risk factors were antimicrobial use, solid tumor malignancy and a CCI score >6.

Validated Risk Score for Predicting 6-Month Mortality in Infective Endocarditis.

BACKGROUND: Host factors and complications have been associated with higher mortality in infective endocarditis (IE). We sought to develop and validate a model of clinical characteristics to predict 6-month mortality in IE. METHODS AND RESULTS: Using a large multinational prospective registry of definite IE (International Collaboration on Endocarditis [ICE]-Prospective Cohort Study [PCS], 2000-2006, n=4049), a model to predict 6-month survival was developed by Cox proportional hazards modeling with inverse probability weighting for surgery treatment and was internally validated by the bootstrapping method. This model was externally validated in an independent prospective registry (ICE-PLUS, 2008-2012, n=1197). The 6-month mortality was 971 of 4049 (24.0%) in the ICE-PCS cohort and 342 of 1197 (28.6%) in the ICE-PLUS cohort. Surgery during the index hospitalization was performed in 48.1% and 54.0% of the cohorts, respectively. In the derivation model, variables related to host factors (age, dialysis), IE characteristics (prosthetic or nosocomial IE, causative organism, left-sided valve vegetation), and IE complications (severe heart failure, stroke, paravalvular complication, and persistent bacteremia) were independently associated with 6-month mortality, and surgery was associated with a lower risk of mortality (Harrell's C statistic 0.715). In the validation model, these variables had similar hazard ratios (Harrell's C statistic 0.682), with a similar, independent benefit of surgery (hazard ratio 0.74, 95% CI 0.62-0.89). A simplified risk model was developed by weight adjustment of these variables. CONCLUSIONS: Six-month mortality after IE is ≈25% and is predicted by host factors, IE characteristics, and IE complications. Surgery during the index hospitalization is associated with lower mortality but is performed less frequently in the highest risk patients. A simplified risk model may be used to identify specific risk subgroups in IE.

Carbapenemase-producing Klebsiella pneumoniae bloodstream infections in neutropenic patients with haematological malignancies or aplastic anaemia: Analysis of 50 cases.

Carbapenemase-producing Klebsiella pneumoniae (CP-Kp) are currently among the most important nosocomial pathogens in many geographic regions. A retrospective study was conducted between 2010 and 2014 in four hospitals located in a high-prevalence area (Athens, Greece) to describe the clinical features, treatment and outcomes of neutropenic patients with haematological diseases complicated with CP-Kp bloodstream infections. A total of 50 patients were identified, including 48 with haematological malignancies and 2 with aplastic anaemia. All patients had neutropenia (<500 cells/mm(3)), of whom 40 had <100 neutrophils/mm(3). The probable source of bacteraemia was identified in 9 patients; in the remaining 41 patients the bacteraemia was considered primary. For definitive treatment, 30 patients received combination therapy (two or more active drugs), 10 received monotherapy (one active drug) and 4 received therapy with no active drug; the remaining 6 patients died within 48 h after the onset of bacteraemia. The 14-day all-cause mortality rate was 50%, 38% and 33% for those who received one, two or three active drugs respectively. In the Cox proportional hazards model, unresolved neutropenia [hazard ratio (HR)=19.28, 95% confidence interval (CI) 2.31-160.69; P=0.006], septic shock (HR=3.04, 95% CI 1.06-8.78; P=0.04) and treatment with one active drug (HR for monotherapy versus combination therapy=3.95, 95% CI 1.23-12.65; P=0.02) were independent predictors of death, whilst combination therapy was associated with lower mortality. These findings may assist physicians in making treatment decisions for neutropenic patients with CP-Kp infections.

Intravascular Lymphoma as an Uncommon Cause of Anasarca.

OBJECTIVES: To report a case of intravascular lymphoma (IVL) in a Caucasian patient who presented with anasarca as his sole clinical sign. MATERIAL AND METHODS: A man presented with anasarca-type oedema and fatigue. After excluding heart failure, hepatic cirrhosis, nephrotic syndrome, hypothyroidism, AL-amyloidosis and adverse drug reaction which can all cause oedema, we turned our attention to capillary permeability disorders. RESULTS: Closer review of the bone marrow aspirate demonstrated haemophagocytic histiocytosis, while core, renal and duodenal biopsies showed a B-cell IVL. CONCLUSION: The differential diagnosis of anasarca, a relatively common clinical sign, should include IVL although the diagnosis may still be challenging. LEARNING POINTS: Anasarca-type oedema is an unusual initial presentation of intravascular lymphoma (IVL) and is normally attributed to capillary permeability disorders.Two clinical forms of IVL have been recognized: a Western form and an Asian variant which is characterized by haemophagocytosis.Patients of Caucasian origin who have the clinical features of the Asian variant of IVL make the diagnosis of this condition even more challenging.

Daptomycin for Gram-positive Infections in Patients with Neutropenia: Clinical Experience from a European Outcomes Registry.

INTRODUCTION: The aim of this analysis was to describe in real-world settings the clinical outcomes and safety associated with daptomycin treatment in patients with neutropenia and Gram-positive infections. METHODS: Patients with an absolute neutrophil count (ANC) ≤1000 cells/mm(3) who received at least one dose of daptomycin between 2006 and 2012 were selected from a non-interventional, multicenter, retrospective registry (European Cubicin(®) Outcome Registry and Experience; EU-CORE(SM)). RESULTS: Of the 6075 patients enrolled in EU-CORE, 446 (7.3%) had an ANC ≤ 1000 cells/mm(3) at baseline or during daptomycin therapy; they were all included in efficacy and safety populations. Half of the patients had severe neutropenia (ANC ≤ 100 cells/mm(3)). Most patients had hematologic malignancy (60.5%), an immunosuppressed state (39.7%) or had undergone a transplant (27.8%). The most common primary infections were bacteremia (42.2%) and complicated skin and soft tissue infection (13.9%). Cultures were positive for 68.6% (254/370) of patients with available culture results; coagulase-negative staphylococci (43.7%; 111/254) and Staphylococcus aureus (18.9%; 48/254) were the most commonly isolated primary pathogens. Median duration of daptomycin therapy was 10.0 (range 1-98) days. Most patients (82.8%) received antibiotics concomitantly with daptomycin; the most common were carbapenems (51.2%), penicillins (42.1%), and aminoglycosides (19.9%). The overall clinical success rate (cured or improved) associated with daptomycin was 77.1%. Adverse events possibly related to daptomycin treatment were reported in seven (1.6%) patients and led to drug discontinuation in 27 (6.1%) patients. CONCLUSION: The study results suggest that daptomycin is an effective therapeutic option for the treatment of a broad range of Gram-positive infections in patients with neutropenia, and has a good safety profile. FUNDING: This study was funded by Novartis Pharma AG.

Determination of colistin A and colistin B in human plasma by UPLC-ESI high resolution tandem MS: application to a pharmacokinetic study.

The resistance of gram-negative bacteria to most available antibiotics and the lack of new antimicrobial agents have prompted the re-emergence of colistin (CS) as potent treatment against most gram-negative microorganisms. Optimal dosing with CS suffers from poor pharmacokinetic characterization mainly due to the analytical challenge of assaying CS in biological fluids and the limited information on quantitative analysis of CS in plasma using high resolution mass spectrometry (MS). Hence, a rapid, simple and accurate analytical method based on ultra performance liquid chromatography (UPLC) combined with electrospray ionization (ESI) tandem mass spectrometry (MS/MS) on a hybrid quadrupole time of flight (QTOF) instrument has been developed and fully validated for the quantification of CS in human plasma. After the pretreatment of plasma samples by solid phase extraction (SPE) and the addition of the internal standard (reserpine, RSP) the analytes were chromatographed on an Acquity BEH C8 column (100 mm × 2.1 mm, 1.7 µm) using gradient elution with 0.5% aqueous acetic acid (AcOH) and acetonitrile with 0.5% AcOH (with CSA and CSB eluting at 1.39 and 1.31 min, respectively). Accurate mass measurement correction was performed on line using the leukine-enkephaline standard. The method presented good fit (regression coefficient≥0.998) over the quantitation range of 0.2-300 and 0.03-4.5 µg mL(-1) with the lower limit of quantitation (LLOQ) being 0.02 and 0.03 µg mL(-1) for CSA and CSB in human plasma, respectively. The intra- and inter-day precision, measured as %relative standard deviation, was better than 10%, whereas the accuracy expressed as %relative error was also better than 10%. The short term, freeze-thaw (three cycles) and in process stability showed non-significant degradation of CS under these conditions. The validation results showed that the developed method demonstrated adequate selectivity and sensitivity. The method has been successfully applied to plasma samples from patients suffering from cystic fibrosis and treated with CS, and the pharmacokinetic profile has been calculated.

Length of exposure to the hospital environment is more important than antibiotic exposure in healthcare associated infections by methicillin-resistant Staphylococcus aureus: a comparative study

OBJECTIVES: Both total antimicrobial use and specific antimicrobials have been implicated as risk factors for healthcare-associated methicillin-resistant Staphylococcus aureus (HCA-MRSA) infection. The aims of this study were: (I) to explore predictors of a new HCA-MRSA infection in comparison with a new healthcare-associated methicillin-sensitive Staphylococcus aureus (HCA-MSSA); (II) to thoroughly assess the role of recent antibiotic use qualitatively and quantitatively. METHODS: The time-period for our study was from October 1997 through September 2001. Through applying strict criteria, we identified two groups of inpatients, one with a new HCA-MRSA infection and one with a new HCA-MSSA infection. We recorded demographic, clinical and antibiotic use-related data up to 30 days before the positive culture date. RESULTS: We identified 127 and 70 patients for each group, respectively. Two logistic regression models were carried out to assess the role of antimicrobial use (qualitatively and quantitatively). In model I, duration of hospital stay, presence of chronic wounds, aminoglycoside and fluoroquinolone use retained statistical significance. In model II, duration of hospital stay and history of intubation during the last month stood out as the only significant predictors of a subsequent HCA-MRSA infection. No significant differences in outcome were noted. CONCLUSIONS: The length of exposure to the hospital environment may be the best predictor of a new HCA-MRSA infection. Use of aminoglycosides and fluoroquinolones may also stand independently along with presence of chronic ulcers and surgical procedures. No independent association between quantitative antibiotic use and subsequent HCA-MRSA infection was documented.

Extranodal natural killer/T-cell lymphoma, nasal-type.

A 51-year-old previously healthy man, an ex-smoker, was admitted to the authors' medical department with a 3-month history of dry cough; intermittent fever; painless, ulcerated cutaneous lesions over the trunk and limbs (Figure 1); and progressive weight loss. He was of Greek descent. His medical history was remarkable for nasal polyps, which were surgically removed 15 years earlier. Initially, he had been treated with antibiotics, without improvement. Several days before admission, chest radiography revealed pulmonary infiltrates in the left lower lobe. On admission, physical examination revealed a well-orientated man in mild distress, with inspiratory rhonchi at the lower part of the left lung and scattered erythematous nodules of variable size, some of which were ulcerated. Laboratory values were notable for leukopenia, 3.3 x 10(9)/L; total protein, 5.9 g/dL; globulin, 2.2 g/dL; serum glutamic oxaloacetic transaminase, 86 IU/L; serum glutamic pyruvic transaminase, 71 IU/L; and lactate dehydrogenase, 519 U/L. Computed tomograph (CT) of the chest showed multiple alveolar opacities bilaterally (Figure 2). Fiberoptic bronchoscopy did not reveal any important pathologic findings. Results of bronchial biopsy, cytology of bronchoalveolar lavage, washing, brushing, and sputum following bronchoscopy were negative. CT of the brai and sinonasal area revealed an abnormal low-density mass in the left nasal area. CT findings of the abdomen were negative, as were results of a bone marrow biopsy. There was no evidence of immunosuppression. The differential diagnosis, considering the evidence described, included granulomatous or infectious diseases, angiocentric lymphoproliferative lesions, and lymphomas. Biopsy of a skin lesion showed lymphoproliferative infiltration of the dermis with a follicular and angiocentric growth pattern and regional epidermal necrosis. Immunohistochemical stains showed that the tumor cell were positive for CD56 and CD3 (cytoplasmic positivity) and expressed the cytotoxic proteins T-cell intracellular antigen and granzyme B (Figure 3) They lacked TdT, CD34, CD7, CD8, TCL-1, and CD123. Findings from an in situ hybridization study for Epstein-Barr virus were negative. Give this result, molecular analysis ofT-cell receptor (TCR) gene rearrangements was performed using polymerase chain reaction-based TCR-gamma gene, wit negative results. The morphology and the immunophenotype were consistent with natural killer/T-cell lymphoma, nasal-type. Nasal involvement must be first excluded to proceed to the diagnosis of nasal-type natural killer-cell lymphoma. Indeed, histologic examination of the nasal mass revealed its polypoid nature. Thus, the authors were led to the diagnosis of extranodal extranasal natural killer/T-cell lymphoma, nasal-type, CD56-positive, Ep stein-Barr virus-negative, TCR-negative. The patient received combination chemotherapy and completed 4 cycles of cyclophosphamide, doxorubicin vincristine, and prednisone every 14 days for 2 months. Skin lesions improved, and there was no fever soon after the initiation of therapy. Reevaluatio after the fourth cycle, however, disclosed pulmonary infiltrations as well as leukemic infiltration of the central nervous system. The patient had receive systemic salvage chemotherapy and intrathecal infusions of methotrexate. Although the lung lesions had diminished at that time, the patient develope paraplegia, his clinical course rapidly deteriorated, and he eventually died.

Fulminant pancytopenia due to cytomegalovirus infection in an immunocompetent adult

A case of severe and irreversible pancytopenia secondary to acute primary cytomegalovirus infection in an immunocompetent woman is described. The patient presented with thrombocytopenia, lymphopenia, anemia, and abnormal liver function tests. Treatment with corticosteroids and intravenous immunoglobulin was ineffective in reconstituting hemopoiesis. The patient developed severe sepsis and eventually expired.

Gastric syphilis: a systematic review of published cases of the last 50 years.

The authors conducted a systematic review of the English literature for cases of Gastric Syphilis (GS) in the last 50 years. The 34 studies which met selection criteria included 52 patients with GS. Of the reviewed patients, only 13% had a history of syphilis diagnosis and 46% had prior or concurrent clinical manifestations of the disease. Epigastric pain/fullness was the most common presenting symptom (92%) and epigastric tenderness being the most common sign. Gastric bleeding of variable intensity was documented in 35% of the cases. In the radiologic examinations, fibrotic narrowing and rigidity of the gastric wall was the most common finding (43%), followed by hypertrophic and irregular folds, while in endoscopy the most common lesion types were multiple ulcerations (48%), nodular mucosa, and erosions. The antrum was the most commonly affected area (56%). The majority of the patients received penicillin (83%) with a rapid resolution of their symptoms. Seventeen percent of the patients were treated surgically either due to a complication or due to strong suspicion of infiltrating tumor or lymphoma. The nonspecific clinical, radiologic, and pathologic characteristics of GS can establish it as a great imitator of other gastric diseases. GS should be considered in the differential diagnosis in patients at risk for sexually transmitted diseases who present with abdominal complaints and unusual endoscopic lesions and no other diagnosis is made, irrespective of the presence of H. pylori. The absence of primary or secondary luetic lesions should not deter one from considering GS.

Course of inflammatory bowel disease in patients infected with human immunodeficiency virus.

BACKGROUND: Human immunodeficiency virus (HIV) infection depletes CD4+ lymphocytes, which may benefit patients with inflammatory bowel disease (IBD). The aim was to compare the course of IBD in HIV patients with a matched group of IBD seronegative patients. METHODS: A total of 20 IBD (14 Crohn's disease, 6 ulcerative colitis) HIV infected patients and 40 matched control seronegative IBD patients (2 controls per case) were compared regarding relapse of their disease. The CD4+ count was followed every 6 months and a value of < or =500 cells/microL was used to define patients with immunosuppression. Relapse rates per year of follow-up were compared among the 2 groups and survival curves for cumulative remission rates were compared with a log-rank test. Multivariate analysis was used to discriminate among the impact of different variables on the risk of IBD relapse. RESULTS: The median duration of follow-up was 8.4 years (range 0.6-18 years). The mean relapse rate for the HIV+IBD group was 0.016/year of follow-up as compared to 0.053/year of follow-up for the IBD-matched control group (P = 0.032). Regarding the HIV-positive/IBD group, 14 patients were immunosuppressed at any given time during the follow-up period. None of these patients experienced an IBD relapse, whereas 3 out of the 6 without immunosuppression relapsed (P = 0.017). According to the multivariate analysis, HIV status was the only risk factor independently associated with a lower probability of IBD relapse. CONCLUSIONS: HIV infection reduces the relapse rates in IBD patients and this may be attributed to the lower CD4+ counts seen in these patients.

Poststernotomy sternal osteomyelitis and mediastinitis by Trichosporon asahii: a rare occurrence with a grave prognosis.

Post-sternotomy infectious complications, including superficial and deep wound infections, sternal osteomyelitis and mediastinitis, are rarely caused by fungi. Trichosporon asahii is the main Trichosporon species that causes systemic infection in humans. Most cases involved neutropenic patients with hematologic malignancies. We report a unique case of a non-cancer, non-neutropenic but severely ill patient who developed an ultimately lethal T. asahii infection after sternotomy. We speculate that our patient had been colonized with the fungus and his surgical site infection may have been related to his emergency revascularization surgery. Therapy with liposomal amphotericin failed to sterilize the bloodstream despite in vitro susceptibility results. The addition of voriconazole helped sterilizing the bloodstream without changing the outcome. Physicians must be aware of the continuously expanding spectrum of infections with this emerging difficult-to-treat fungal pathogen.

Long-term complete regression of nodal marginal zone lymphoma transformed into diffuse large B-cell lymphoma with highly active antiretroviral therapy alone in human immunodeficiency virus infection.

Since the introduction of combination antiretroviral therapy (cART), there has been a decrease in the incidence of non-Hodgkin lymphoma among the HIV-infected population and also significantly improved survival rates. We describe a remarkable case of a HIV-infected patient whose large B-cell lymphoma, most likely arising by transformation of a nodal marginal zone lymphoma, completely regressed with the use of cART alone. He remained disease-free for almost 3 years and he finally died from presumed flare up of his lymphoma. There are very few cases of spontaneous regression of lymphomas with cART alone in the HIV population. This is an extreme example of the significance of cART in improving survival in HIV-non-Hodgkin lymphoma and changing the face of the HIV epidemic in general.

Community-acquired methicillin-resistant Staphylococcus aureus as a cause of rapidly progressing pyelonephritis with pyonephrosis, necessitating emergent nephrectomy.

In this article, we describe the first, to our knowledge, reported case of severe bacteremic upper urinary tract infection with pyonephrosis-in the context of prior chronic urinary tract disease-caused by community-acquired methicillin-resistant Staphylococcus aureus (MRSA). The patient presented with fever and constitutional symptoms, and computed tomography revealed extensive renal parenchymal infection along with a staghorn calculus and dilatation of the pyelocalyceal system. His clinical condition rapidly deteriorated, and he developed uncontrollable sepsis, necessitating an emergent nephrectomy. Significant pyonephrosis was noted during surgery. Blood cultures yielded MRSA, and molecular analysis (by polymerase chain reaction) of the MRSA strains from blood and wound fluid showed that they were Panton-Valentine leukocidin positive and they also possessed SCCmecA type IV. Postoperatively, the patient was treated with intravenous vancomycin for 3 weeks and had a favorable outcome.

Fatal rhizopus pneumonia in allogeneic stem cell transplant patients despite posaconazole prophylaxis: two cases and review of the literature.

Posaconazole is a triazole with broad spectrum of activity against multiple fungi including members of the fungal order Mucorales. This activity has been shown both in clinical and in vitro studies, which are critically reviewed here. It has become very popular in prophylaxis in acute myelogenous leukemia (AML) induction and in the graft-versus-host disease (GVHD) settings after 2 recent prospective trials that showed advantage of posaconazole prophylaxis compared to fluconazole or itraconazole. In this report, 2 patients are presented, in whom, despite posaconazole prophylaxis, invasive and ultimately fatal Rhizopus pulmonary infections developed. These cases are similar to a previously reported case of Rhizopus infection in a stem cell transplant recipient who also received posaconazole, indicating a potential newly recognized pattern of breakthrough infections in patients receiving posaconazole prophylaxis.

Primary sternal osteomyelitis caused by Nocardia nova: case report and literature review.

A 51 year old woman without significant past medical history or risk factors for Nocardia infection developed primary Nocardia nova sternal osteomyelitis with mediastinal abscess, diagnosed with open biopsy. She required prolonged antibiotic therapy and had a favorable outcome. Primary sternal osteomyelitis develops in the absence of a contiguous focus of infection, as opposed to secondary sternal osteomyelitis, which is usually a complication of sternotomy. Staphylococcus aureus probably still is the most common cause of both forms of sternal osteomyelitis. Nocardia species invade humans usually through the respiratory tract and can cause a variety of localized infections through the hematogenous route. Pulmonary involvement may or may not coexist. Immunosuppressed patients are more prone to infection by Nocardia species, although cases involving seemingly immunocompetent patients are not rare. This is the first reported case in the English literature of primary sternal osteomyelitis due to Nocardia nova or any other Nocardia species.

Primary sternal osteomyelitis caused by Nocardia nova: case report and literature review

A 51 year old woman without significant past medical history or risk factors for Nocardia infection developed primary Nocardia nova sternal osteomyelitis with mediastinal abscess, diagnosed with open biopsy. She required prolonged antibiotic therapy and had a favorable outcome. Primary sternal osteomyelitis develops in the absence of a contiguous focus of infection, as opposed to secondary sternal osteomyelitis, which is usually a complication of sternotomy. Staphylococcus aureus probably still is the most common cause of both forms of sternal osteomyelitis. Nocardia species invade humans usually through the respiratory tract and can cause a variety of localized infections through the hematogenous route. Pulmonary involvement may or may not coexist. Immunosuppressed patients are more prone to infection by Nocardia species, although cases involving seemingly immunocompetent patients are not rare. This is the first reported case in the English literature of primary sternal osteomyelitis due to Nocardia nova or any other Nocardia species.