Infections due to Lancefield group C streptococci.

Our experience with group C streptococcal infection over the past 15 years demonstrates an important and emerging role for this hemolytic organism as an opportunistic and nosocomial pathogen. Significant risk factors in this predominantly male population included chronic cardiopulmonary disease, diabetes, malignancy, and alcoholism. Bacteremia occurred in 74% of cases seen in our series. Nosocomial acquisition of infection was observed in 26%, and infection was frequently polymicrobial in nature with gram-negative enteric bacilli isolated most commonly along with group C streptococci. We observed a broad spectrum of infections including puerperal sepsis, pleuropulmonary infections, skin and soft-tissue infection, central nervous system infection, endocarditis, urinary tract infection, and pharyngeal infections. Several cases of bacteremia of unknown source were observed in neutropenic patients with underlying leukemia. New syndromes of infection due to group C streptococci observed in our series included intra-abdominal abscess, epidural abscess, and dialysis-associated infection. Response to therapy and outcome was related to the underlying disease. While the literature suggests that patients with group C endocarditis respond better to synergistic penicillin-aminoglycoside regimens, patient numbers are too small to draw definite conclusions. The clinical significance of antibiotic tolerant group C streptococci remains uncertain. In patients with serious group C infections including endocarditis, meningitis, septic arthritis, or bacteremia in neutropenic hosts, we advocate the initial use of cell-wall-acting agents in combination with an aminoglycoside.

The lumpy jaw. Cervicofacial actinomycosis.

Cervicofacial actinomycosis is a unique polymicrobic infection of endogenous origin, displaying a highly variable clinical course, ranging from an acute, suppurative lesion to a chronic fibrotic process more suggestive of a malignancy. Lesions advance with total disregard for tissue planes, producing burrowing sinus tracts to the skin or mucosal surfaces, which often discharge sulfur granules, colonies of Actinomyces species cemented together by host phosphatase activity. The diagnosis is quite elusive when proper studies (anaerobic culture, careful tissue examination and fluorescent antibody stains) are not undertaken in a timely fashion. Most cases respond well to a prolonged course of antimicrobial therapy. Some patients require excision of fibrotic lesions or persistent sinus tracts. Penicillin G is considered the agent of choice on the basis of extensive clinical experience; tetracycline, erythromycin, and clindamycin are effective as alternative agents.

Left-sided endocarditis due to Pseudomonas aeruginosa. A report of 10 cases and review of the literature.

Ten confirmed cases of left-sided endocarditis due to Pseudomonas aeruginosa were reported in detail and the English literature was reviewed. In recent years, venous access (usually illicit) has been the major predisposing factor to this infection and abuse of pentazocine and tripelennamine has been particularly associated with endocarditis due to this organism. This infection involves previously damaged as well as normal valves. The development of congestive heart failure did not adversely affect the prognosis of this infection. However, the development of azotemia was associated with a greater likelihood of a fatal outcome. In the current series, deaths were due to uncontrolled infection. This often occurred despite inhibitory and bactericidal activity in serum generally considered adequate for treatment of endocarditis. Medical treatment alone rarely produced cure of infection. Our experience with a high frequency of major vessel embolization (4/10) and the improved survival after medical/surgical treatment suggests that prompt valve replacement combined with high doses of an aminoglycoside plus carbenicillin or ticarcillin provide the best opportunity for successful outcome in patients with left-sided endocarditis due to P. aeruginosa.

Infections due to Lancefield group G streptococci.

The group G streptococcus has surfaced in the past 10 to 15 years as an important opportunistic and nosocomial pathogen. Although more precise organism recognition accounts for a portion of these cases, there can be little doubt that the group G streptococcus has become a more prevalent pathogen. Commercial kits, utilizing staphylococcal coagglutination or latex agglutination, are now available, affording all clinical laboratories the opportunity to identify this organism easily. Published reviews encompassing the experiences of a single institution or even several institutions affiliated with a single medical center, particularly as they were influenced by referral patterns, did not reflect the broad scope of infections that we discovered by extending our survey into the community, beyond the medical center complex and its immediate affiliated hospitals. Although malignancy is the single most obvious background factor, alcoholism and diabetes are also important host determinants of infection. Skin and soft-tissue infections (and surface sources of infection) are equally important among patients with or without the element of malignancy. Polymicrobial infection, including polymicrobial bacteremia, is an important feature, with S. aureus infections accounting for most of these cases, relating to the skin and soft tissue sources of infections so commonly seen. We saw a panorama of problems including endocarditis, septic arthritis, pleuropulmonary infections, bone and joint infections, puerperal sepsis and neonatal infection, peritonitis and ophthalmitis; we also saw a significant number of patients with bacteremia and no apparent primary source of infection. Response to antibiotic therapy was dictated by the nature of the underlying diseases, and individuals without a background of malignant disease did well, particularly those with skin and soft-tissue infections. While the literature suggests that patients with endocarditis and septic arthritis due to this organism respond poorly to antibiotic therapy, implying that such failures relate to in vitro antibiotic phenomena, we preferred to examine the problem from the viewpoint of the host(s) involved. Subacute endocarditis and acute endocarditis due to the group G streptococcus may be clinically separable, and thus require separate therapeutic approaches. In patients with septic arthritis, prosthetic devices, prior joint disease and immunosuppressive diseases and therapy often adversely influence the response to antibiotic therapy.(ABSTRACT TRUNCATED AT 400 WORDS)

Neurologic complications of infective endocarditis.

Neurologic complications continue to occur in approximately 30 per cent of all patients with infective endocarditis and represent a major factor associated with an increased mortality rate in that disease. Of these complications, cerebral embolism is the most common and the most important, occurring in as many as 30 per cent of all patients, most of whom ultimately die. Emboli that are infected also account for all the other complications (mycotic aneurysm, meningitis or meningoencephalitis, brain abscess) that may develop. Emboli are more common in patients with mitral valve infection and in those infected with more virulent organisms. Mycotic aneurysms (often preceded by an embolic event) occur more frequently and earlier in the course of acute endocarditis, rather than later, which is more common in the course of subacute disease. The management of a cerebral mycotic aneurysm depends on the presence or absence of hemorrhage, its anatomic location and the clinical course. Healing can occur during the course of effective antimicrobial therapy and thus will preclude the need for automatic surgery in all angiographically demonstrated aneurysms. The indication for surgical intervention must be evaluated on an individual basis. Meningitis is usually purulent when associated with virulent organisms, but the CSF may present an aseptic formula when associated with subarachnoid hemorrhage or multiple microscopic embolic lesions, infected or otherwise. Macroscopic brain abscesses are rare, but multiple microscopic abscesses are not uncommon in patients with acute endocarditis due to virulent organisms. Seizures are not uncommon in patients with infective endocarditis. Focal seizures are more commonly associated with acute emboli, whereas generalized seizures are more commonly associated with systemic metabolic factors. Penicillin neurotoxicity should be considered in seizure patients with compromised renal function who are receiving high doses of penicillin. The CSF tends to reflect the nature of the infecting organism rather than the nature of the neurologic complication, except when hemorrhage is present. Endocarditis due to virulent organisms, such as Staphylococcus aureus, is usually associated with a purulent CSF formula, whereas non-virulent organisms, such as "viridans" streptococci, usually have aseptic or normal CSF formulas.

EF-4 bacteremia in a patient with hepatic carcinoid.

An organism similar to EF-4, a member of the unclassified group of unusual gram-negative bacilli of Elizabeth O. King, was isolated from the blood of a 65-year-old female with previously diagnosed carcinoid of the liver. We believe this to be the first report of systemic infection with this organism.

Capnocytophaga bacteremia in the compromised host.

Capnocytophaga, a CO2-requiring gram-negative bacillus, is a recently recognized pathogen in the immunocompromised host. The authors present two cases with granulocytopenia, oral disease and bacteremia with Capnocytophage ochracea. The microbiology of this genus, its clinical association with periodontal disease, granulocytopenia and oral ulceration, and its implications for the compromised host are reviewed.

Haemophilus influenzae meningitis: the spectrum of disease in adults.

Fifteen cases of Haemophilus influenzae (HI) meningitis in adults occurring of Cleveland during the last 11 years are presented. The majority of patients had factors predisposing to infection such as otitis, pneumonia, diabetes or alcoholism. In addition, 7 of the 15 patients developed meningitis at various intervals following head trauma and neurosurgery, and 3 patients required dural repairs for CSF rhinorrhea. The diagnosis of meningitis may be difficult to establish resulting in delay in appropriate therapy in some cases. Nuchal rigidity was absent frequently; CSF lymphocytosis can be seen initially. The CSF Gram stain may be negative or the pleomorphic nature of the organism on Gram-stain may make distinction from other gram-negative organisms difficult. The majority of patients had meningitis due to non-Type B HI in contrast to previous reports of this illness in children and adults. One of our patients had beta-lactamase producing HI isolated from CSF. We believe that chloramphenicol should be included in the initial empiric therapy for adults with meningitis and gram-negative coccobacillary rods on Gram-stain or negative CSF Gram-stains.

Infections due to Lancefield group F and related Streptococci (S. milleri, S. anginosus).

We can no longer accept classification of streptococci solely on the basis of hemolytic reactions or Lancefield agglutinations. While the "viridans" streptococci cannot be serologically differentiated, physiological separation of the species offers a satisfactory method of classifying human isolates. We review the microbiology of Lancefield group F and related streptococci (S. milleri, S. anginosus), emphasizing microbial ecology and current taxonomic considerations. A series of 28 patients infected with these organisms is presented. There was a striking male predominance in the series (6:1) as well as an obvious association with underlying diseases and/or antecedent trauma. The most remarkable feature of these pathogens is their predilection for abscess formation, confirming their overdue recognition as the most common "viridans" streptococcus recovered from abscesses within internal organs. We observed purulent disease of the nervous and skeletal systems, oral cavity, lung and pleural space, abdomen and subcutaneous tissues. Microbial synergy (i.e. polymicrobic infection) was not a requisite for abscess formation. Four of the five deaths in this series occurred in patients 60 years of age of older. Some degree of variability in antimicrobial susceptibility was noted, so speciation alone may not always provide sufficient information on which to base a therapeutic decision.

Infective endocarditis caused by slow-growing, fastidious, Gram-negative bacteria.

In a review of endocarditis caused by fastidious, slow-growing gram-negative rods, similarities in the spectrum of disease overshadow differences among cases grouped by specific organisms. Cardiobacterium hominis, Actinobacillus actinomycetemcomitans and Haemophilus species usually seed previously damaged cardiac valves presumably during bacteremia from an upper respiratory site. The clinical presentation resembles that of Streptococcus viridans endocarditis and is usually subacute or chronic. Despite bacteriologic cure, severe CHF and/or systemic embolization frequently develops during or following the course of antibiotics, resulting in significant morbidity and a high mortality rate. This report of nine cases diagnosed at five hospitals in a 7-year period suggests that endocarditis due to these organisms is more common than previously appreciated and frequently goes unrecognized. This is probably due to a lack of attention to the requirements for culture of this group of bacteria with propensity for granular growth in broth. We have proposed specific cultural techniques appropriate to the search for these organisms in patients with apparent culture-negative endocarditis.