Cerebral tuberculosis in patients with the acquired immunodeficiency syndrome (AIDS). Report of 6 cases and review

Management of intracranial tuberculous mass lesions: how long should we treat for?

Tuberculous intracranial mass lesions are common in settings with high tuberculosis (TB) incidence and HIV prevalence. The diagnosis of such lesions, which include tuberculoma and tuberculous abscesses, is often presumptive and based on radiological features, supportive evidence of TB elsewhere and response to TB treatment. However, the treatment response is unpredictable, with lesions frequently enlarging paradoxically or persisting for many years despite appropriate TB treatment and corticosteroid therapy. Most international guidelines recommend a 9-12 month course of TB treatment for central nervous system TB when the infecting Mycobacterium tuberculosis ( M.tb) strain is sensitive to first-line drugs. However, there is variation in opinion and practice with respect to the duration of TB treatment in patients with tuberculomas or tuberculous abscesses. A major reason for this is the lack of prospective clinical trial evidence. Some experts suggest continuing treatment until radiological resolution of enhancing lesions has been achieved, but this may unnecessarily expose patients to prolonged periods of potentially toxic drugs. It is currently unknown whether persistent radiological enhancement of intracranial tuberculomas after 9-12 months of treatment represents active disease, inflammatory response in a sterilized lesion or merely revascularization. The consequences of stopping TB treatment prior to resolution of lesional enhancement have rarely been explored. These important issues were discussed at the 3 rd International Tuberculous Meningitis Consortium meeting. Most clinicians were of the opinion that continued enhancement does not necessarily represent treatment failure and that prolonged TB therapy was not warranted in patients presumably infected with M.tb strains susceptible to first-line drugs. In this manuscript we highlight current medical treatment practices, benefits and disadvantages of different TB treatment durations and the need for evidence-based guidelines regarding the treatment duration of patients with intracranial tuberculous mass lesions.

Management of intracranial tuberculous mass lesions: how long should we treat for?

Tuberculous intracranial mass lesions are common in settings with high tuberculosis (TB) incidence and HIV prevalence. The diagnosis of such lesions, which include tuberculoma and tuberculous abscesses, is often presumptive and based on radiological features, supportive evidence of TB elsewhere and response to TB treatment. However, the treatment response is unpredictable, with lesions frequently enlarging paradoxically or persisting for many years despite appropriate TB treatment and corticosteroid therapy. Most international guidelines recommend a 9-12 month course of TB treatment for central nervous system TB when the infecting Mycobacterium tuberculosis ( M.tb) strain is sensitive to first-line drugs. However, there is variation in opinion and practice with respect to the duration of TB treatment in patients with tuberculomas or tuberculous abscesses. A major reason for this is the lack of prospective clinical trial evidence. Some experts suggest continuing treatment until radiological resolution of enhancing lesions has been achieved, but this may unnecessarily expose patients to prolonged periods of potentially toxic drugs. It is currently unknown whether persistent radiological enhancement of intracranial tuberculomas after 9-12 months of treatment represents active disease, inflammatory response in a sterilized lesion or merely revascularization. The consequences of stopping TB treatment prior to resolution of lesional enhancement have rarely been explored. These important issues were discussed at the 3 rd International Tuberculous Meningitis Consortium meeting. Most clinicians were of the opinion that continued enhancement does not necessarily represent treatment failure and that prolonged TB therapy was not warranted in patients presumably infected with M.tb strains susceptible to first-line drugs. In this manuscript we highlight current medical treatment practices, benefits and disadvantages of different TB treatment durations and the need for evidence-based guidelines regarding the treatment duration of patients with intracranial tuberculous mass lesions.

Management of intracranial tuberculous mass lesions: how long should we treat for?

Tuberculous intracranial mass lesions are common in settings with high tuberculosis (TB) incidence and HIV prevalence. The diagnosis of such lesions, which include tuberculoma and tuberculous abscesses, is often presumptive and based on radiological features, supportive evidence of TB elsewhere and response to TB treatment. However, the treatment response is unpredictable, with lesions frequently enlarging paradoxically or persisting for many years despite appropriate TB treatment and corticosteroid therapy. Most international guidelines recommend a 9-12 month course of TB treatment for central nervous system TB when the infecting Mycobacterium tuberculosis (M.tb) strain is sensitive to first-line drugs. However, there is variation in opinion and practice with respect to the duration of TB treatment in patients with tuberculomas or tuberculous abscesses. A major reason for this is the lack of prospective clinical trial evidence. Some experts suggest continuing treatment until radiological resolution of enhancing lesions has been achieved, but this may unnecessarily expose patients to prolonged periods of potentially toxic drugs. It is currently unknown whether persistent radiological enhancement of intracranial tuberculomas after 9-12 months of treatment represents active disease, inflammatory response in a sterilized lesion or merely revascularization. The consequences of stopping TB treatment prior to resolution of lesional enhancement have rarely been explored. These important issues were discussed at the 3rd International Tuberculous Meningitis Consortium meeting. Most clinicians were of the opinion that continued enhancement does not necessarily represent treatment failure and that prolonged TB therapy was not warranted in patients presumably infected with M.tb strains susceptible to first-line drugs. In this manuscript we highlight current medical treatment practices, benefits and disadvantages of different TB treatment durations and the need for evidence-based guidelines regarding the treatment duration of patients with intracranial tuberculous mass lesions.

Central Nervous System Tuberculosis : Etiology, Clinical Manifestations and Neuroradiological Features

PURPOSE

As a result of multilateral migration and globalization in times of humanitarian crises, western countries face a possible increase in the incidence of central nervous system tuberculosis (CNS TB). The diagnosis of CNS TB is challenging and often delayed due to the manifold and often non-specific presentation of the disease. The aim of this review is to analyze and summarize imaging features and correlated clinical findings of CNS TB.

METHODS

The different manifestations of CNS TB are explained and illustrated by characteristic neuroradiological as well as neuropathological findings. An overview on diagnostic and therapeutic approaches is provided. For clarity, tables summarizing the lesion patterns, differential diagnoses and diagnostic hints are added.

RESULTS

The CNS TB can be manifested (1) diffuse as tuberculous meningitis (TBM), (2) localized as tuberculoma or (3) tuberculous abscess or (4) in extradural and intradural spinal infections. Information on clinical presentation, underlying pathology and the distinguishing features is demonstrated. The TBM is further described, which may lead to cranial nerve palsy, hydrocephalus and infarction due to associated arteritis of the basal perforators. The differential diagnoses are vast and include other infections, such as bacterial, viral or fungal meningoencephalitis, malignant causes or systemic inflammation with CNS. Complicating factors of diagnosis and treatment are HIV coinfection, multi-drug resistance and TB-associated immune reconstitution inflammatory syndrome (IRIS).

CONCLUSIONS

Neurologists and (neuro-)radiologists should be familiar with the neuroradiological presentation and the clinical course of CNS TB to ensure timely diagnosis and treatment.

Imaging studies of the HIV-infected brain

Human immunodeficiency virus (HIV) enters the brain early after infecting humans and may remain in the central nervous system despite successful antiretroviral treatment. Many neuroimaging techniques were used to study HIV+ patients with or without opportunistic infections. These techniques assessed abnormalities in brain structures (using computed tomography, structural magnetic resonance imaging (MRI), diffusion MRI) and function (using functional MRI at rest or during a task, and perfusion MRI with or without a contrast agent). In addition, single-photon emission computed tomography with various tracers (e.g., thallium-201, Tc99-HMPAO) and positron emission tomography with various agents (e.g., [18F]-dexoyglucose, [11C]-PiB, and [11C]-TSPO tracers), were applied to study opportunistic infections or HIV-associated neurocognitive disorders. Neuroimaging provides diagnoses and biomarkers to quantitate the severity of brain injury or to monitor treatment effects, and may yield insights into the pathophysiology of HIV infection. As the majority of antiretroviral-stable HIV+ patients are living longer, age-related comorbid disorders (e.g., additional neuroinflammation, cerebrovascular disorders, or other dementias) will need to be considered. Other highly prevalent conditions, such as substance use disorders, psychiatric illnesses, and the long-term effects of combined antiretroviral therapy, all may lead to additional brain injury. Neuroimaging studies could provide knowledge regarding how these comorbid conditions impact the HIV-infected brain. Lastly, specific molecular imaging agents may be needed to assess the central nervous system viral reservoir.

Bacterial pathogens

Bacterial infections are frequent complications among patients treated for cancer. The type, severity, and treatment of bacterial infections vary and depend upon the specific malignancy, associated chemotherapies, and transplantation. This chapter discusses commonly encountered bacterial pathogens as well as Nocardia and mycobacteria in patients with cancer and addresses the clinical syndromes and management. Drug-resistant bacteria are becoming an increasingly recognized problem in patients with cancer. Antimicrobial resistance in select gram-positive and gram-negative bacteria are discussed along with the mechanisms of resistance and recommended therapies.

Effect of rehabilitation on a patient suffering from a tuberculous brain abscess with Gerstmann's syndrome: case report

There are few reports in the literature of tuberculous brain abscess. Tuberculous brain abscess usually occurs in an immunocompromised host. Almost all previously documented cases have involved acquired immune deficiency syndrome. We encountered a 53-year-old right-handed immunocompetent male who was initially suspected of having a cerebrovascular accident due to acute-onset right hemiparesis and paresthesia. A tentative diagnosis of brain tumor versus brain abscess was made on imaging studies. The patient was finally diagnosed with a tuberculous brain abscess based upon deterioration on imaging and a positive tuberculosis culture. The tuberculous brain abscess was located in the left parietal lobe, which resulted in Gerstmann's syndrome and right-sided apraxia. Stereotactic surgery was performed. He was also given antituberculosis chemotherapy and comprehensive rehabilitation. Considerable improvement was noted after rehabilitation. The patient even returned to a normal life and work. Our case demonstrates that an aggressive intensive inpatient rehabilitation program combined with stereotactic surgery and effective antituberculosis therapy play an important role in improving the outcome for patients with tuberculous brain abscess, Gerstmann's syndrome, and right-sided apraxia.

Rhombencephalitis: a series of 97 patients

The term rhombencephalitis refers to inflammatory diseases affecting the hindbrain (brainstem and cerebellum). Rhombencephalitis has a wide variety of etiologies, some of them potentially severe and life threatening without proper early treatment. In this retrospective observational study, we reviewed the records of consecutively hospitalized patients at University Hospital of Bellvitge (Barcelona, Spain) from January 1990 to December 2008. Rhombencephalitis was defined as a brainstem and/or cerebellar condition demonstrated clinically or by neuroimaging, with pleocytosis (>4 cells/mm) in cerebrospinal fluid. Ninety-seven patients (48 female; mean age, 37 yr; range, 14-79 yr) fulfilled these criteria. We reviewed their clinical, cerebrospinal fluid, and radiologic characteristics. The mean follow-up was 5 years (range, 0-20 yr). The etiologies of rhombencephalitis were as follows: unknown cause (n = 31), multiple sclerosis (n = 28), Behçet disease (n = 10), Listeria monocytogenes infection (n = 9), paraneoplastic syndrome (n = 6) (3 cases associated with anti-Yo antibodies and 3 with anti-Tr antibodies), Epstein-Barr virus (n = 4), tuberculosis (n = 2), pneumococcal infection (n = 2), systemic lupus erythematosus (n = 1), lymphoma (n = 1), Brucella species infection (n = 1), JC virus (n = 1), and relapsing polychondritis (n = 1). Certain clinical, cerebrospinal fluid, and radiologic characteristics that are commonly seen in some of these etiologies can guide us in the first approach to the etiologic diagnosis of rhombencephalitis.

[Neurotuberculosis: a continuing clinical challenge]

In Germany neurotuberculosis is quite rare. Familiarity with the disease is nonetheless important because of many differential diagnoses and therapeutic implications. The diagnosis of neurotuberculosis is made by considering of clinical presentation, CSF, and cerebral imaging. Early diagnosis, prompt initiation of effective antitubercular therapy, and clinical staging are necessary for establishing a long-term treatment prognosis. The results of neurotuberculosis therapy are often unsatisfactory despite the availability of effective drugs. Lasting damage or death can be averted in fewer than half of the patients. Studies now confirm that early adjuvant corticoid therapy reduces lethality and morbidity. Resistant new strains of the pathogen, Mycobacterium tuberculosis, complicate therapy. Recent discoveries especially in diagnosis and therapy are explained using case evidence.

Immune reconstitution syndrome in a patient with AIDS with paradoxically deteriorating brain tuberculoma

A 54-year-old man with an underlying AIDS experienced fever and lethargy. Magnetic resonance imaging (MRI) showed multiple small ring-enhancement lesions over pons, basal ganglion, thalami, and bilateral cerebral hemisphere. Because of the concurrent pulmonary tuberculosis (TB), presumptive diagnosis of tuberculous meningitis and brain tuberculoma was made. The patient's condition clinically improved after a 3-month anti-TB treatment coupled with highly active antiretroviral therapy (HAART), and his CD4-T lymphocyte count was increased from 17 cells/mm(3) (HIV viral load, 294,000 copies per milliliter) to 153 cells/mm(3) (HIV viral load, 5930 copies per milliliter). However, the follow-up MRI disclosed disappearance of some old brain lesions and development of some new ones; some previously identified tuberculoma became smaller in size, while some other enlarger. Of note, ring-enhanced brain lesions were found over the left frontal lobe and left posterior fossa with perifocal edema and hyperintensity in diffusion weighted MRI indicating abscess formation. Steroid was added based on the presumed paradoxical reaction of brain tuberculoma. Complete resolution of brain lesions was found on MRI 9 months later. Tuberculoma should be considered in a patient with AIDS with numerous intracranial lesions if TB involving other site(s) is definitively diagnosed, especially when the patient is receiving prophylactic trimethoprim-sulfamethoxazole and/or serologically negative for toxoplasmosis. Our report demonstrated the peculiar phenomenon of paradoxical reaction of brain tuberculoma during immune reconstitution and strengthens the belief that additional use of steroids for paradoxical reaction of brain tuberculoma is indicated after exclusion of other causes for the progressively enlarging brain lesions.

Tuberculous brain abscess in AIDS patients: report of three cases and literature review

OBJECTIVE

Clinical description of tuberculous brain abscess in patients with acquired immunodeficiency syndrome (AIDS).

METHODS

Clinical case report and review of the literature from January 1981 to January 2003 using the MEDLINE database.

RESULTS

The authors report three cases of tuberculous brain abscess in AIDS patients and review nine similar cases. The mean age was 30 years (range: 18-56 years) with seven patients being male. Five (42%) were intravenous drug users, had prior history of extra-cerebral tuberculosis, and presented alterations on chest radiograph. Tuberculin skin test was anergic in six (75%) of eight patients. Three patients of nine had a CD4+ cell count higher than 200 cells/microL, and three had a CD4+ cell count lower than 100 cells/microl. All but one patient had a brain computerized tomography scan with a single lesion. All patients received anti-tuberculous treatment and underwent surgical procedures. Most patients (75%) showed appropriate clinical responses.

CONCLUSION

Tuberculous brain abscess must be considered in the differential diagnosis of intracranial mass in AIDS patients. A careful epidemiological, clinical and laboratory evaluation may guide a diagnostic suspicion. Surgery combined with specific anti-tuberculosis treatment seems to determine a good outcome.

Cerebral tuberculomas in AIDS patients: a forgotten diagnosis?

The human immunodeficiency virus (HIV) infection epidemics increased the prevalence, multi-drug resistance and disseminated forms of tuberculosis. The central nervous system (CNS) tuberculosis has high mortality and morbidity, and it is usually divided into diffuse (meningitis) and localized (tuberculoma and abscess) forms. We report three cases of cerebral tuberculomas in AIDS patients: one with definitive diagnosis, confirmed with histopathology, and two with probable diagnosis, based on clinical information, radiological images, Mycobaterium tuberculosis isolation out of the CNS and adequate response to antituberculous treatment. Further, we discuss diagnostic, therapeutic and prognostic issues of tuberculomas, with emphasis in the distinction from cerebral tuberculous abscesses. Despite of their infrequent presentation, tuberculomas should be considered in the differential diagnosis of cerebral expansive lesions in patients with AIDS.

New Times for an Old Disease: Intracranial Mass Lesions Caused by Mycobacterium tuberculosis in 5 HIV-Negative African Immigrants

BACKGROUND

The tuberculosis epidemic is still a global emergency, and its spread in the past 20 years has been fueled by the acquired immune deficiency syndrome pandemic and increasing drug resistance. International travel and migration may increase the incidence of tuberculosis in industrialized countries.

METHODS

We reviewed the clinical charts of patients admitted to the infectious diseases unit of Ospedali Riuniti (Bergamo, Italy) to identify patients with intracranial mass lesions caused by Mycobacterium tuberculosis.

RESULTS

During the past 6.5 years, 5 of 30 patients with a mass of infectious origin in the brain had tuberculous brain lesions diagnosed. All 5 were human immunodeficiency virus (HIV)-negative adults and African immigrants. No patient had concomitant meningitis, 1 had a concomitant pulmonary disease, and 3 subjects reported a past history of tuberculosis. At presentation, no patient had fever and 3 had seizures. Examination of cerebrospinal fluid revealed normal findings for 4 of 4 subjects, and neuroimaging showed multiple intracranial mass lesions in 4 of 5 patients. The diagnosis was definite for 2 subjects (based on analysis of brain specimens) and presumptive for 3 subjects (1 had concomitant pulmonary tuberculosis, and 2 had clinical response to therapy). Results of susceptibility tests for M. tuberculosis were available for 2 patients: both isolates were resistant to isoniazid, and 1 was also resistant to streptomycin. Duration of medical treatment ranged from 11 to 23 months, and 2 subjects underwent surgical procedures at the time of diagnosis. All 5 patients recovered.

CONCLUSIONS

Clinicians in western countries should consider the possible role of tuberculosis in causing mass lesions in the brain, particularly in immigrants from regions where tuberculosis is endemic.

Paradoxical reaction to the treatment of tuberculosis uncovering previously silent meningeal disease

The development of paradoxical clinical worsening following initiation of tuberculosis treatment may complicate the clinical course of both HIV-infected and uninfected patients. We report a severe manifestation of the so called paradoxical reaction to the treatment of tuberculosis that unmasked previously silent meningeal disease in a 34-year-old HIV-infected male patient.

Generalized tuberculosis in the acquired immune deficiency syndrome

OBJECTIVE

Generalized, or hematogenously disseminated, tuberculosis (TB) in patients with the acquired immune deficiency syndrome (AIDS) has been associated with a high incidence of cases remaining undiagnosed until postmortem. To better characterize generalized TB in the setting of AIDS, this report describes the clinical, laboratory, radiologic, and pathologic features of 20 fatal cases.

DESIGN

The medical records, autopsy protocols, and histologic material from patients with AIDS and concomitant TB were reviewed. All patients were autopsied at a tertiary care medical center during the years 1985-1997.

RESULTS

In 50% of our 20 cases, diagnosis was not made until postmortem. Signs and symptoms were few, including the absence of fever (temperature > or = 38 degrees C) in 55% of patients. Consistent laboratory abnormalities of a nonspecific nature were limited to hyponatremia (sodium <135 mmol/L) in 60%. Both peripheral and deep (thoracic and abdominal) lymphadenopathy, unusual in adults with TB, occurred in 45% and 95% of cases, respectively. In contrast to previous reports, all of the 6 cases of tuberculous meningitis presented as acute meningitis with a predominance of neutrophils in cerebrospinal fluid. Necrotizing encephalitis with extension of the acute inflammation into the superficial cortex was seen in all cases and tuberculous brain abscesses occurred in 50% of cases, a higher frequency than previously reported. Despite lung involvement in 90% of the cases, 33% of chest radiographs were interpreted as normal and disseminated mycobacterial disease was not suggested in the radiograph report in any of the other cases. Soft tissue abscesses in uncharacteristic locations such as the neck, mediastinum, and perirectal area occurred in these patients. Histologically, 95% of organs sampled showed inflammatory foci characterized by extensive necrosis with numerous neutrophils and/or karyorrhectic debris, numerous acid-fast bacilli, few or no epithelioid histiocytes, and no Langhans giant cells.

CONCLUSION

Clinically and pathologically, generalized TB in the setting of AIDS is characterized by either unusual features or a lack of the typical features described for generalized TB in patients who do not have AIDS. This absence of classic features contributes to the high incidence of cases that remain undiagnosed until postmortem examination.

Immune restoration disease after the treatment of immunodeficient HIV-infected patients with highly active antiretroviral therapy

BACKGROUND

To determine if infectious disease events in HIV-infected patients treated with highly active antiretroviral therapy (HAART) are a consequence of the restoration of pathogen-specific immune responses, a single-centre retrospective study of all HIV-infected patients commencing HAART prior to 1 July 1997 was undertaken to determine the incidence, characteristics and time of onset of disease episodes in HAART responders (decrease in plasma HIV RNA of > 1 log10 copies/mL).

METHODS

Baseline and post-therapy changes in CD4 T-cell counts and HIV RNA were compared in patients with and without disease and delayed-type hypersensitivity responses to mycobacterial antigens were measured in selected patients.

RESULTS

Thirty-three of 132 HAART responders (25%) exhibited one or more disease episodes after HAART, related to a pre-existent or subclinical infection by an opportunistic pathogen. Disease episodes were most often related to infections by mycobacteria or herpesviruses but hepatitis C virus (HCV), molluscum contagiosum virus and human papilloma virus were also implicated. They were most common in patients with a baseline CD4 T-cell count of < 50/uL and occurred most often during the first 2 months of therapy and when CD4 T-cell counts were increasing. Mycobacteria- and HCV-related diseases were associated with restoration of pathogen-specific immune responses.

CONCLUSIONS

We conclude that improved immune function in immunodeficient patients treated with HAART may restore pathogen-specific immune responses and cause inflammation in tissues infected by those pathogens.