Hematogenous spread

Congenital syphilis is a condition in which the fetus is infected with T. pallidum as a result of the hematogenous spread from an infected mother, although transmission may also occur from direct contact with the infectious genitalia of the mother. Since the primary stage of syphilis is characterized by spirochetemia, infectious rates of the fetus are nearly 100% if the mother has primary syphilis.11... 

Metastatic spread can occur by local extension, lymphatic drainage, or hematogenous dissemination.17 Lymph node metastases are more common in patients with large, undifferentiated tumors that invade the seminal vesicles. The pelvic and abdominal lymph node groups are the most common sites of lymph node involvement (Fig. 89-1). Skeletal metastases from hematogenous spread are the most common sites of distant... 

A delicate balance of normal pressure is maintained in the brain and spinal cord by brain, blood, and cerebrospinal fluid (CSF) volume. Since the brain is contained within a confined space (skull), any foreign mass contained within that space causes adverse sequelae. This results in either destruction or displacement of normal brain tissue with associated edema. Most brain metastases occur through hematogenous spread of the primary tumor, and around 80% of patients will have multiple sites of metastases within the brain. 

Infections are the result of hematogenous spread from a primary infection site, seeding from a parameningeal focus, reactivation from a latent site, trauma, or congenital defects in the CNS. 

Approximately 10% of patients develop reactivation disease, which arises subsequent to the hematogenous spread of the organism. In the United States, most cases of TB are believed to result from reactivation. Occasionally, a massive inoculum of organisms may be introduced into the bloodstream, causing widely disseminated disease and granuloma formation known as miliary TB. 

The exact mechanism of bacterial infection of the prostate is not well understood. The possible routes of infection include ascending infection of the urethra, reflux of infected urine into prostatic ducts, invasion by rectal bacteria through direct extension or lymphatic spread, and by hematogenous spread. 

The risk for infectious arthritis is high in patients with autoimmune diseases with compromised immunity. Acute bacterial arthritis mostly results from hematogenous spread in the elderly and in the less than 15 years. Acute monarthritis should raise a high index of suspicion of joint infection. 

Tularemia pneumonia can result from an inhalation exposure or from hematogenous spread of the infection. An aerosol release could be expected to result in large numbers of patients experiencing systemic symptoms accompanied by signs and symptoms associated with one or more of the following conditions pharyngitis, bronchiolitis, pleuropneumonitis and hilar lymphadenitis (43). However, many people with inhalational exposure will likely develop a clinical presentation of systemic symptoms without prominent signs or symptoms of respiratory disease. 

The development of IE via hematogenous spread, the most common route, requires the sequential occurrence of several factors. These components are complex and not fully elucidated ... 

The most common cause of osteomyelitis (particularly that acquired by hematogenous spread) and infectious arthritis is Staphylococcus aureus. 

Disease may remain localized in the lungs or may disseminate to other tissues, particularly the CNS, although the skin also can be affected. Hematogenous spread generally occurs in the immunocompromised host, although it also has been seen in individuals with intact immune systems. Cryptococcemia is the most common symptomatic extraneural infection associated with C. neoformans. Cryptococcemia can be documented in 5% to 22% of non-AIDS patients, and CNS involvement of C. neoformans can be fonnd in 18% to 50% of AIDS patients. Cryptococcal disease is present in 7.5% to 10% of AIDS patients. Therefore, patients with evidence of extranenral cryptococcosis should be evaluated for CNS disease. 

About 20% of patients with colorectal cancer present with metastatic disease. Metastatic spread occnrs as a resnlt of direct m-mor invasion of adjacent tissues or by lymphatic or hematogenous spread. The venous drainage of the colon and rectnm inflnences the... 

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