Fatal HIV encephalitis in HIV-seronegative patients

Seronegative HIV-1 infection in a Japanese man presenting with Pneumocystis pneumonia: Analysis of long-term antibody response and literature review

Seronegative human immunodeficiency virus (HIV) infection, where an HIV-specific antibody response is lacking even in chronic or late-stage HIV infections, is extremely rare. Here, we report the case of a 50-year-old Japanese man presenting with Pneumocystis pneumonia who did not produce antibodies against HIV-1 until the initiation of antiretroviral therapy (ART). Fourth-generation antigen-antibody testing temporarily reverted from weakly positive to negative soon after initiating ART, likely due to a reduction in viral load (assessed by p24 antigen levels). His HIV-1 antibody titers remained low or indeterminate even after four years of ART. A literature review suggested that the absence of HIV-1-specific antibody production may be associated with unimpeded HIV replication and rapid CD4+ T cell decline. Seronegative HIV infection can lead to deferred diagnosis and treatment, thereby increasing the risk of transmitting the virus to others or developing opportunistic illnesses. It is important to combine multiple tests for diagnosis, depending on the medical condition. Further studies are required to investigate the host factors involved in the production of HIV-1-specific antibodies.

Acute HIV-1 infection presenting with fulminant encephalopathy

Human immunodeficiency virus (HIV)-1 directly affects the nervous system, causes distinct neurological symptoms, and indirectly results in opportunistic infections, which include herpes virus simplex (HSV)-1, HSV-2, varicella zoster virus, and cytomegalovirus encephalitis caused by immunodeficiency. Early HIV-1 invasion of the central nervous system is also possible, and acute encephalopathy is a potentially lethal complication. We encountered a case of fulminant encephalopathy as a primary presentation of acute HIV-1 infection, in which highly active antiretroviral treatment resulted in a full clinical recovery. This case highlights the importance of considering acute HIV-1 infection in the differential diagnosis of reversible encephalopathy.

Fatal pulmonary Kaposi sarcoma in an HIV seronegative AIDS patient

INTRODUCTION

Although HIV antibody tests have been widely accepted in clinical diagnosis of HIV infection, they may not be sufficient to diagnose all subjects with HIV infection. Except negative result of antibody test in the well-known" acute window phase", in rare cases, patients do not develop HIV antibodies despite demonstrable infection. Primary pulmonary Kaposi sarcoma (KS) without mucocutaneous involvement accounts for only 0-15% of all AIDS-related KS. KS is rare among Chinese subjects, especially in persons of Han descent.

METHODS

A case of seronegative AIDS with primary pulmonary Kaposi sarcoma (KS) was reported. It's a 46-year-old Chinese man presented with sore throat, hemoptysis, fever, dyspnea and multiple lung nodules. The lung lesions grew over a 5-month period so as the symptoms worsened. The possibility of AIDS was discounted by his physicians because of the repeatedly negative HIV antibodies tests despite the ELISA tests or Western blot tests. Histopathologic diagnosis of fine needle lung biopsy in local hospital was undetermined. After admission, HIV infection was eventually confirmed by plasma HIV RNA testing. Histopathologic diagnosis of Lung Kaposi sarcoma was made through repeated fine needle aspiration biopsy as well as the review of former one. Multiple antibiotics and chemotherapy were administrated with no clinical effect due to advanced stage and the patient passed away soon after diagnosis.

RESULTS

This is the first case of seronegative HIV-1 infection with presentation of primary pulmonary KS.

CONCLUSION

This case underscores the importance of plasma RNA test in conjunction with HIV antibody test for some rare patients with HIV infection who present with severe immunodeficiency and opportunistic infections or malignancy.

Acute encephalitis as initial presentation of primary HIV infection

Acute encephalitis is a life-threatening condition. A wide variety of infectious agents are implicated and in many patients no cause is found. HIV acute seroconversion illness can rarely present as acute encephalitis. Although most experts agree in starting antiretroviral treatment in severe acute HIV infection, the evidence of the benefits are still lacking. The authors report a case of severe acute encephalitis as a primary presentation of HIV infection in which introduction of highly active antiretroviral treatment resulted in clinical recovery. This case highlights the need to consider HIV infection in the differential diagnosis of treatable viral encephalitis.