Underlying cardiac lesions in adults with infective endocarditis. The changing spectrum.

The spectrum of recognized cardiac lesions underlying infective endocarditis has been changing as a result of the decline in incidence of rheumatic heart disease, the recognition of the entity of mitral valve prolapse, and the improvement in cardiac diagnostic techniques. Sixty-three cases of native valve endocarditis diagnosed in Memphis hospitals between 1980 and 1984 were reviewed. All diagnoses of underlying cardiac lesions were confirmed by two-dimensional echocardiography, cardiac catheterization, and/or histopathologic examination of valve tissues. Major categories of underlying lesions were as follows: mitral valve prolapse, 29 percent; no underlying disease, 27 percent; degenerative lesions of the aortic or mitral valve, 21 percent; congenital heart disease, 13 percent; rheumatic heart disease, 6 percent. Thus, mitral valve prolapse and, in the elderly, degenerative lesions have displaced rheumatic and congenital heart diseases as the major conditions underlying endocarditis. Redundancy of the mitral valve leaflets was noted in 17 of 18 patients in whom endocarditis was superimposed upon mitral valve prolapse. The risk of infective endocarditis appears to be substantially increased in the subset of patients with mitral valve prolapse who exhibit valvular redundancy.

Recurrent massive pleural effusion due to pleural, pericardial, and epicardial fibrosis in histoplasmosis.

Acute histoplasmosis is generally a benign, self-limited pulmonary infection. Although Histoplasma capsulatum pneumonitis is common, pleural effusions associated with histoplasmosis are quite rare, and massive pleural effusions have not been reported. There have been several reports of pericardial fibrosis secondary to histoplasmosis, but epicardial fibrosis has not been described. We report a biopsy-proven case of histoplasmosis initially associated with recurrent massive pleural effusions and excessive pleural fibrosis causing a trapped lung. The patient later developed constrictive pericarditis. Despite pericardiectomy, severe cor pulmonale occurred, and the patient died. Necropsy demonstrated fibrosis of the epicardium.

The effect of a portable HEPA-filtered body exhaust system on airborne microbial contamination in a conventional operating room.

OBJECTIVE: To study the effect of a portable HEPA-filtered air exhaust system (Stackhouse Freedom Surgical Helmet System) on airborne microbial contamination in a modern conventional operating room. DESIGN AND SETTING: Microbial air sampling was done with a two-stage Anderson sampler at the wound site during 46 total joint replacements. All operations were performed by the same surgeon in the same operating room at a large community hospital. RESULTS: In 18 cases done without air exhaust hoods, the number of bacterial and fungal colony-forming units (CFU) ranged from 0.6 to 11.7 (mean, 3.6). Air sampling during 28 operations with the operating team in air exhaust hoods revealed a mean of 3.6 CFU (range, 0 to 11.4). Bacterial CFU averaged 3.4 without hoods and 3.2 with exhaust hoods. Coagulase-negative staphylococci were the most common isolates (48% of isolates with hood, 55% without hood). No infections occurred. CONCLUSION: We concluded that these air exhaust hoods did not lower airborne microbial contamination detectable with this air sampling method, as compared to standard head cover and mask, in a modern conventional operating room.

Histoplasmosis in patients with acquired immunodeficiency syndrome. Hematologic and bone marrow manifestations.

In areas where Histoplasma capsulatum infections are endemic in the United States, there is an increasing frequency of progressive disseminated histoplasmosis (PDH) as an opportunistic infection in patients with acquired immune deficiency syndrome (AIDS). The bone marrow and peripheral blood (PB) specimens in 13 patients with AIDS and PDH were reviewed. Anemia, leukopenia, and thrombocytopenia were found in 12, 10, and 7 patients, respectively. Circulating organisms were detected in the blood smears or buffy coat preparations from five patients and were associated with PB nRBCs and severe absolute monocytopenia. Morphologically, the marrow specimens showed one of four patterns: (1) no morphologic evidence of infection (two patients, one with a positive marrow culture); (2) discrete granulomas (two patients, both with positive marrow cultures); (3) lymphohistiocytic aggregates (six patients, four with positive marrow cultures); and (4) diffuse macrophage infiltrates (three patients, all with positive marrow cultures). Morphologic examination of the bone marrow combined with cultures is useful in diagnosing disseminated histoplasmosis in patients with AIDS. However, the morphologic findings in the bone marrow may be different in patients with AIDS compared with non-AIDS patients, and seemingly nondiagnostic morphologic features must be approached with a high degree of suspicion in diagnosing infections with H. capsulatum in this population.

Hydroxyurea in combination with didanosine and stavudine in antiretroviral-experienced HIV-infected subjects with a review of the literature.

The safety and efficacy of hydroxyurea with didanosine in combination with stavudine in nucleoside reverse-transcriptase inhibitor (NRTI)-experienced patients was investigated. Entry criteria included HIV-1 infected, NRTI-experienced adults, with CD4(+) counts 50-550 cells/mm(3) and viral loads >or=12,500 copies/mL. Subjects were treated with didanosine 200 mg twice a day (BID), stavudine 40 mg BID, and hydroxyurea 1000 mg daily for 16 weeks. Thirty-one HIV-1 subjects with mean bDNA viral load 1x10(5) log(10) copies/mL and mean CD4(+) T-cell counts of 231 cells/mm(3) were enrolled. A 1.3 log(10) decrease in mean viral load was seen at 12 weeks of therapy. Prior didanosine use resulted in a more rapid response to therapy compared with prior zidovudine use. Side effects consisting of neutropenia, pancreatitis, and peripheral neuropathy occurred in four subjects and resolved upon withdrawal of therapy. This non-randomized study in subjects with a mean CD4(+) T-cell count of 230 cells/mm(3) demonstrates the antiviral activity of hydroxyurea+didanosine and stavudine. Toxicities related to therapy need to be followed closely. The results support the need for a randomized, prospective study to determine the safety and efficacy of hydroxyurea plus didanosine in antiretroviral-experienced patients with CD4(+) cell counts below 300 cells/mm(3).

Histoplasmosis in AIDS: advances in management.

Histoplasmosis is one of the most common opportunistic infections in HIV-infected patients who reside in endemic areas, and "imported infections" also occur elsewhere. A recent decline in the incidence of histoplasmosis appears to correlate with advances in antiretroviral therapy. Histoplasmosis occurs due to either dissemination of newly acquired infection or reactivation of latent foci of infection. Major risk factors include a CD4 count < or = 150/microL, positive complement fixation serology for the Histoplasma capsulatum mycelial antigen, and a history of exposure to chicken coops; in addition, suboptimal antiretroviral therapy seems likely to be a risk factor. Although there are a variety of clinical manifestations, most patients present with a several-week history of fever, chills, weakness, and weight loss. Diagnosis is based on positive cultures of blood, bone marrow, or other sites; detection of antigen in serum or urine; or characteristic histopathologic findings in biopsy specimens. Induction therapy consists of amphotericin B for acutely ill patients or itraconazole for patients with mild to moderately severe disease. Subsequent lifelong maintenance therapy with itraconazole is recommended. In patients with CD4 counts of < or = 150/microL, itraconazole is effective primary prophylaxis.

Histoplasmosis in Missouri: historical review and current clinical concepts.

Histoplasmosis is particularly common in Missouri, and many important clinical observations about the disease were made in this state in the 1950s and 1960s. When the AIDS epidemic spread to Missouri in the mid-1980s, histoplasmosis became recognized as a common and important opportunistic infection among Missourians with AIDS. Clinicians must maintain a high level of suspicion for histoplasmosis in any HIV-infected patient who presents with unexplained fever, particularly if the patient has evidence of hepatosplenomegaly, generalized lymphadenopathy, pancytopenia, abnormal liver function tests, or bilateral pulmonary infiltrates. The diagnosis of histoplasmosis can be established rapidly by observation of organisms on peripheral blood smear or bone marrow biopsy specimens or by Histoplasma Polysaccharide Antigen testing. The diagnosis can be confirmed by blood cultures in most cases. Histoplasmosis in AIDS is invariably fatal if not treated. Treatment consists of two phases: initial induction therapy and subsequent lifelong maintenance therapy. Amphotericin B and itraconazole are extremely effective for induction and maintenance therapy; fluconazole appears to be effective maintenance therapy. Strategies for the prevention of histoplasmosis in high risk patients are being evaluated currently.

A prospective study of 2,092 "curbside" questions asked of two infectious disease consultants in private practice in the midwest.

We prospectively studied 2,092 consecutive informal (or "curbside") consultations (CCs) posed of two infectious disease (ID) consultants in private practice in different cities. The frequency of CCs was similar for the two physicians: 31 and 30 per month. The majority of CCs (69%) were initiated by staff physicians, of whom 47% were engaged in primary care. The average duration of CCs was 5.1 minutes overall and increased significantly from 3 minutes in 1990 to 7 minutes in 1994 for one consultant (P < .0001). Overall, 52% of questions asked by staff physicians were considered inappropriate (on the basis of their complexity); this rate increased from 40% in 1990 to 53% in 1994 for one physician (P = .005). Although a variety of subject matters were represented, questions concerning treatment of specific infections were the most common. We conclude that the demand for community-based ID physicians' informal advice remains significant. Any need-assessment for the practice of these specialists in the community should take into account their often unrecognized direct and indirect contribution to the care of many patients they never formally see.

Detection of the source of recurrent Staphylococcus aureus bacteremia by ultrafast computerized tomography.

A patient with spina bifida secondary to an Arnold-Chiari deformity experienced seven episodes of sustained bacteremia due to Staphylococcus aureus over 2 years. Despite an extensive diagnostic evaluation the source of the recurrent bacteremia remained obscure. The patient's mother eventually recalled that a procedure for replacement of a ventriculoatrial shunt performed 16 years earlier had been complicated by retention of a shunt fragment in the bloodstream. Standard radiographic techniques failed to identify an intravascular foreign body; however, ultrafast computerized tomography of the heart demonstrated a density in the right atrium. Atriotomy was performed and a plastic catheter fragment was excised. Bacteremia has not recurred during a follow-up period of 24 months. Patients with recurrent unexplained bacteremia should be evaluated carefully for the presence of occult intravascular catheter fragments that may be retained after surgical procedures or intravascular instrumentation. Ultrafast computed tomographic scanning of the heart is a useful technique for detecting intracardiac catheter fragments.

Immune complex glomerulonephritis associated with Staphylococcus aureus bacteremia: response to corticosteroid therapy.

Immune complex glomerulonephritis developed in a patient with high-grade Staphylococcus aureus bacteremia. Renal function declined steadily despite treatment with a prolonged course of bactericidal antimicrobial agents and apparent cure of the staphylococcal infection. Following initiation of corticosteroid therapy, renal function improved dramatically. Judicious use of corticosteroids should be considered in patients with persistent renal dysfunction secondary to infection-associated immune complex glomerulonephritis.

Colonic histoplasmosis in acquired immunodeficiency syndrome. Report of two cases.

Colonic histoplasmosis is a rare entity. There have been four previous reported cases within the population of patients with human immunodeficiency virus (HIV) infection. Because of the increasing incidence of HIV infection within regions where histoplasmosis is endemic, this condition may become more common. Gastrointestinal histoplasmosis has protean clinical manifestations, and symptoms are often nonspecific. Any patient with HIV infection who has unexplained GI symptoms should undergo evaluation for possible histoplasmosis. Aggressive long-term amphotericin B therapy has been effective in HIV patients with histoplasmosis. Resection or diversion of symptomatic colonic strictures caused by histoplasmosis may be necessary in addition to medical therapy.

Protective immunity evoked by locally administered group A streptococcal vaccines in mice.

The present studies were undertaken to determine the pathogenicity of group A streptococci introduced intranasally (i.n.) into mice in an attempt to mimic mucosal infections in humans and to determine the efficacy of streptococcal vaccines administered via the mucosal route. The LD50 of type 24 streptococci (M24 strep) administered i.n. was 3 x 10(4) CFU. Throat cultures were performed in M24 strep-inoculated mice. Of 11 mice that died, 9 had positive throat cultures 3 or 4 days after i.n. challenge, and of 9 mice that survived, only 1 had a positive throat culture, indicating an association between mucosal infection and death. Postmortem examination performed on 35 mice that died after i.n. challenge showed that all had evidence of disseminated infections, and group A streptococci were recovered from the cervical lymph nodes, blood, spleen, liver, and brain. To determine vaccine efficacy, heat-killed M24 strep or pep M24 were administered i.n. to groups of mice. Whole, heat-killed streptococci and pep M24 administered locally protected mice against death from i.n. challenge infections with homologous M24 strep. The whole cell vaccine also protected against i.n. challenge infections with heterologous type 6 streptococci. Our data suggest that streptococcal vaccines administered locally evoke protective immunity against streptococcal infections.

Meningococcal pneumonia: characterization and review of cases seen over the past 25 years.

Fifty-eight cases of meningococcal pneumonia were included in this review. Fifty cases previously described in the literature from 1974 through 1998 and 8 new cases were included in this series. The median age of patients was 57.5 years, and pleuritic chest pain was described in 21 (53.9%) of 39 cases. Blood cultures were positive in 42 (79.3%) of 53 cases for which results were mentioned. Despite the presence of bacteremia, patients did not develop the syndrome of meningococcemia with its associated complications. Serogroup Y meningococci were most commonly recovered and accounted for 44.2% of identified isolates. Therapy has dramatically changed over the past 25 years; prior to 1991, penicillin antibiotics were most often used. Since 1991, 12 (80%) of 15 patients received cephalosporin antibiotics. Only 5 (8.62%) of 58 patients died. Secondary cases of meningococcal infections following exposure to patients with meningococcal pneumonia were noted in 2 instances.

Long-term amphotericin B therapy for disseminated histoplasmosis in patients with the acquired immunodeficiency syndrome (AIDS).

STUDY OBJECTIVE: To assess the efficacy and toxicity of long-term maintenance amphotericin B therapy in preventing relapses after treatment in patients with the acquired immunodeficiency syndrome (AIDS) and disseminated histoplasmosis. DESIGN: Open, nonrandomized pilot study. SETTING: Three private, university-affiliated community hospitals. PATIENTS: We studied 22 consecutive patients with disseminated histoplasmosis and human immunodeficiency virus (HIV) infection. Sixteen patients completed the study, 5 patients died before completing the initial intensive phase of treatment, and 1 patient received a different treatment regimen. INTERVENTIONS: Seven patients were treated with an initial intensive course of 1000 mg of amphotericin B, followed by weekly infusions of 50 to 80 mg until a cumulative dose of 2000 mg was attained; biweekly infusions of 50 to 80 mg were then continued indefinitely. Nine patients received an initial amphotericin B course of 2000 mg followed by weekly infusions of 80 mg. MEASUREMENTS AND MAIN RESULTS: Of the 7 patients in the 1000-mg intensive regimen group, 6 patients have survived without clinical or laboratory evidence of a histoplasmosis relapse, and 1 died of unrelated causes. Of the 9 patients in the 2000-mg intensive regimen group, 7 patients have survived, 1 patient died of a histoplasmosis relapse, and 1 patient died of other causes. Thus, 13 of 14 patients (93%) who did not die of other causes remained relapse-free. The median follow-up period was 14 months (range, 2 to 23 months). No apparent differences in outcome were observed between patients treated with weekly maintenance regimens and those treated with biweekly maintenance regimens. Sixty-three percent of patients developed intravascular device-related complications. CONCLUSIONS: Long-term, intermittent maintenance amphotericin B therapy in HIV-infected patients with disseminated histoplasmosis is well tolerated and is highly effective in suppressing relapses after treatment.

Mycobacterium kansasii among patients infected with human immunodeficiency virus in Kansas City. Kansas City AIDS Research Consortium.

Previous reports of infection due to Mycobacterium kansasii among patients infected with human immunodeficiency virus (HIV) have conflicted with regard to the significance of the isolate; the clinical, radiographic, and laboratory features of the disease; and the response to therapy. To clarify the spectrum of M. kansasii infection in this population, we conducted a retrospective study of 35 patients. Twenty-eight of these patients were believed to have disease due to M. kansasii, while the remaining seven patients were probably colonized with the organism. All but two patients presented with advanced HIV infection; the median CD4 cell count was 12/microL. Most patients with pulmonary disease presented with fever, cough, and dyspnea, but only eight of these 22 patients had radiographic findings of either pulmonary cavitation or predominantly upper-lobe disease. Ten patients had M. kansasii isolated from blood or bone marrow. The majority of patients with pulmonary or disseminated disease responded to therapy. However, 11 patients died either before mycobacterial infection was diagnosed or early in the course of treatment, and two had a relapse of infection during therapy.

Treatment of lymphocutaneous and visceral sporotrichosis with fluconazole.

Thirty patients with documented sporotrichosis were treated with 200-800 mg of fluconazole daily. Fourteen patients had lymphocutaneous infection; only five (36%) of these patients had any underlying illnesses. Sixteen patients had osteoarticular or visceral sporotrichosis; 12 (75%) of these patients had underlying diseases, mostly alcoholism, diabetes mellitus, and chronic obstructive pulmonary disease. Eleven of the 30 patients had relapsed after prior antifungal therapy. Most patients were treated with 400 mg of fluconazole; however, four received 200 mg of fluconazole daily for the entire course, and four received 800 mg of fluconazole daily for a portion of their therapy or for the entire course of therapy. Fluconazole therapy cured 10 (71%) of 14 patients with lymphocutaneous sporotrichosis. However, only five (31%) of 16 patients with osteoarticular or visceral sporotrichosis responded to therapy; the conditions of two of these five patients improved only, and there was no documented cure of their infections. With the exception of alopecia in five patients, toxic effects were minimal. Fluconazole is only modestly effective for treatment of sporotrichosis and should be considered second-line therapy for the occasional patient who is unable to take itraconazole.