Tags: Doxycycline

Giardia: Clinical Syndromes

After ingestion of G lamblia cysts, 5-15% of patients will have asymptomatic cyst passage, and 25-50% of patients will have diarrhea. From 35% to 70% of these patients will have no evidence of infection. The three manifestations of infection include asymptomatic cyst passage, self-limited diarrhea, and chronic diarrhea with associated malabsorption and weight loss. Factors related to each of these manifestations are unknown but are believed to be related to specific host factors, parasite load, and virulence variation among G lamblia isolates.

Non-falciparum Malaria (P Vivax, P Ovale, P Malariae)

Patients with nonfalciparum malaria invariably develop fever and chills that may become cyclic. Initially, patients experience chills, which are followed by fever (Box 1). Patients with malaria often manifest many nonspecific symptoms such as weakness, malaise, headache, and myalgias. As the disease progresses, signs of anemia, such as pale conjunctiva, may be seen.

Bartonella

There are currently 11 known species of Bartonella, four of which are considered to be pathogenic in humans, namely B bacilliformis, B quintana, B henselae, and Bartonella elizabethae. B henselae and B elizabethae have only recently been isolated and identified, but B quintana and B bacilliformis have long been known as the causes of trench fever (B quintana) and Oroya fever and verruga peruana (B bacilliformis). The bartonellae establish intimate relationships with animal hosts, often within the vascular compartment but without causing disease. The relationship between B bacilliformis and the other three Bartonella species that are pathogenic in humans was established in the early 1990s.

Fever & Bacteremia/Trench Fever/Endocarditis

Patients complain of fever, myalgias, malaise, headache, bone pain — particularly of the legs, and a transient macular rash. Usually the illness continues for 4-6 weeks.

Rocky Mountain Spotted Fever (RMSF)

RMSF is caused by Rickettsia rickettsii and is an acute tick-borne illness occurring during seasonal tick activity. The disease is characterized by acute onset of fever, headache, and a rash of the extremities spreading to the trunk. A. Epidemiology.

Ehrlichia Infection (Ehrlichiosis)

Ehrlichiosis is not a reportable disease, so its true incidence is unknown. The majority of cases of HME have been reported from the south, central, and southeastern United States. Cases have also been reported from Western Europe, Scandinavia, and Africa. In contrast, most cases of HGE have been reported from the upper midwestern and northeastern United States.

Coxiella, Ehrlichia, & Rickettsia

Once inside a host cell, Coxiella and Ehrlichia spp. remain within a vacuole where they progress through distinct developmental stages; in contrast, the Rickettsia spp. escape the endocytic vacuole and replicate within the host cell cytoplasm. Ehrlichia and Rickettsia spp. are transmitted by arthropod vectors. Coxiella burnetii is the causative agent of Query or Q fever.

Chlamydia

Chlamydia trachomatis, Chlamydia psittaci, and Chlamydia pneumoniae are among the most prevalent microbial pathogens in humans worldwide. C trachomatis is responsible for a variety of sexually transmitted disease (STD) syndromes in both sexes. In addition, certain serotypes of C trachomatis are responsible for trachoma, the most common infectious cause of blindness in humans. C psittaci is a zoonotic pathogen associated with atypical pneumonia.