Recurrent UTIs linked to acute psychosis in schizophrenia
By Rita Buckley
Recurrent urinary tract infections (UTIs) may be common in schizophrenic patients with acute psychosis, according to a small study.
Schizophrenia is known to be associated with an increased risk of infections, and studies have found a link between acute psychotic relapse and an elevated prevalence of UTI.
It's not clear whether acute psychosis in schizophrenia is linked to recurrent UTIs, however, Dr. Brian J. Miller and colleagues from Georgia Regents University in Augusta write in a letter to the editor in Schizophrenia Research, online March 10.
The team reviewed the medical records of 152 patients with at least two hospitalizations between 2008-2013 for schizophrenia or schizoaffective disorder.
Twenty-five patients, or 16%, had two or more UTIs, defined as positive leukocyte esterase and/or nitrates and at least 5-10 leukocytes/high-powered field on urinalysis.
These patients had a UTI on 59% (64/109) of their admissions. They also had significantly higher absolute monocyte and eosinophil counts, and lower differential lymphocyte count during admissions with UTI versus without it.
The authors also confirmed a prior finding of theirs, that blood differential WBC counts distinguish patients with UTI versus those without it, indicating a possible link between infection and psychosis.
"Our findings need to be replicated by other groups, but they suggest an increased prevalence of UTIs in patients with acute psychosis," Dr. Miller told Reuters Health by email.
Potential mechanisms that underlie the link remain largely unknown, but there are several possibilities, he said.
One is that acute psychosis may result in physiological changes to the urinary tract that predispose subjects to UTIs. Another is the impact of potential behavioral changes, such as impaired personal hygiene or heightened impulsivity.
Psychiatric treatment may also be involved -- for instance, antipsychotics may cause urinary retention, which increases the risk of UTIs -- as may antibodies triggered by recurrent infections that can cross-react with antigens in the brain via a mechanism called molecular mimicry.
"A proportion of patients with schizophrenia have increased prevalence of a number of autoantibodies," Dr. Miller said.
In vulnerable patients, the host inflammatory response to infection may also result in a worsening of neuropsychiatric symptoms. According to this theory, UTI precedes and is a precipitating factor for acute psychosis.
"Several case reports of resolution of acute psychosis with antibiotic treatment of UTIs are consistent with our clinical experience," he said.
In rare cases, antibiotic treatment may also cause psychiatric symptoms, including psychosis. This is known as "antibiomania," Dr. Miller explained.
Dr. Peter F. Buckley, a psychiatrist at the Medical College of Georgia at Georgia Regents University who has collaborated with Dr. Miller but was not involved in the new study, also noted several possible mechanisms.
"It may well be that infections occur at the same time as relapse because the patient is or was immunocompromised at the time of psychosis," he told Reuters Health by email.
According to Dr. Buckley, people with schizophrenia may have an immune dysfunction that is associated with -- or even responsible, in part -- for their condition. He stressed that psychiatrists should be aware of the heightened risk of infections and physical illness in patients who are psychotic.
Urinalysis is commonly included in laboratory evaluations of acutely ill patients with psychiatric disorders, but UTIs often go untreated and unrecognized. This study, Dr. Miller said, highlights the potential importance of screening for UTIs in this patient population.
According to the researcher, patients with acute psychosis and a urinalysis suggestive of infection should undergo further evaluation, such as a urine culture or inquiries about urinary symptoms.
"Psychiatrists need to be vigilant to the physical health needs of patients as well as their mental health. The relation between psychosis and higher risk of physical illnesses and infection is more than chance," Dr. Buckley agreed.
Schizophr Res 2015.
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