Tom Heller

Dr. Tom Heller

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
5 April 2022 in Open Forum Infectious Diseases
Verified
Journal Article
Open access
PDF file
JOJoep J van Oosterhout
Joep J van Oosterhout
CCChifundo Chipungu
Chifundo Chipungu
LNLyse Nkhoma
Lyse Nkhoma
HKHope Kanise
Hope Kanise
MHMina Hosseinipour
Mina Hosseinipour
THTom Heller
Tom Heller
Dolutegravir HIV drug resistance (HIVDR) data from Africa remain sparse. We reviewed HIVDR results of Malawians on dolutegravir-based antiretroviral therapy (November 2020–September 2021). Of 6462 eligible clients, 33 samples were submitted to South Africa, 27 were sequenced successfully, and 8 (30%) had dolutegravir HIVDR. Malawi urgently requires adequate HIVDR testing capacity.

8 March 2022 in Annals of Global Health
Verified
Journal Article
Open access
PDF file
THTom Heller
Tom Heller
DDDouglas Damba
Douglas Damba
TKTapiwa Kumwenda
Tapiwa Kumwenda
JHJacqueline Huwa
Jacqueline Huwa
CKChristine Kamamia
Christine Kamamia
HTHannock Tweya
Hannock Tweya
100 bed medical ward in referral hospital, Lilongwe, Malawi. HIV positive patients admitted to hospital often have advanced HIV disease (AHD) and are at risk for mortality. WHO guidelines suggest a package of care for AHD; these are often not implemented, especially in inpatient settings. We describe an implementation model for AHD care, its outcomes in routine care and provide cost estimates. An “AHD care room” was established staffed by HIV counselor, nurse, and clinical officer allowing Provider Initiated Testing and Counseling, diagnostic testing for AHD and ensuring availability of HIV and TB drugs for rapid treatment initiation. In the observation period from January to December 2020, a total of 1549 medical inpatients were tested for HIV (coverage 77.1%); 69 tested positive (yield 4.5%). The total proportion of HIV positive was 32.3% (638 already on ART and 69 newly diagnosed). CD4+ testing was done in 460 medical inpatients (65.1%); 245 (53.2%) were below 200 cells/ml and thus met definition of AHD. A total of 238 received S-CrAg tests; 39 (16.3%) were positive; 62 (28.3%) of 219 U-LAM tests were positive. The cost per identification of HIV positive patient was US$ 110.8; per AHD diagnosis between US$ 17.1 to 78.9; per positive S-CrAg test US$ 18.5 and per positive U-LAM test US$ 17.5. Our model successfully implemented AHD services according to WHO guidelines and provides basic costing data. Similar services could be implemented in other hospitals in LMICs.

23 December 2023 in Viruses
Verified
Journal Article
Open access
PDF file
HKHope Kanise
Hope Kanise
JOJoep J van Oosterhout
Joep J van Oosterhout
PBPachawo Bisani
Pachawo Bisani
JSJohn Songo
John Songo
BMBilaal W. Matola
Bilaal W. Matola
THTom Heller
Tom Heller
Millions of Africans are on dolutegravir-based antiretroviral therapy (ART), but few detailed descriptions of dolutegravir resistance and its clinical management exist. We reviewed HIV drug resistance (HIVDR) testing application forms submitted between June 2019 and October 2022, data from the national HIVDR database, and genotypic test results. We obtained standardized ART outcomes and virological results of cases with dolutegravir resistance, and explored associations with dolutegravir resistance among individuals with successful integrase sequencing. All cases were on two nucleoside reverse transcriptase inhibitors (NRTIs)/dolutegravir, and had confirmed virological failure, generally with prolonged viremia. Among 89 samples with successful integrase sequencing, 24 showed dolutegravir resistance. Dolutegravir resistance-associated mutations included R263K (16/24), E138K (7/24), and G118R (6/24). In multivariable logistic regression analysis, older age and the presence of high-level NRTI resistance were significantly associated with dolutegravir resistance. After treatment modification recommendations, four individuals (17%) with dolutegravir resistance died, one self-discontinued ART, one defaulted, and one transferred out. Of the 17 remaining individuals, 12 had follow-up VL results, and 11 (92%) were <1000 copies/mL. Twenty-four cases with dolutegravir resistance among 89 individuals with confirmed virological failure suggests a considerable prevalence in the Malawi HIV program. Successful management of dolutegravir resistance was possible, but early mortality was high. More research on the management of treatment-experienced individuals with dolutegravir resistance is needed.

3 February 2023 in The Ultrasound Journal
Verified
Journal Article
Open access
PDF file
THTom Heller
Tom Heller
FTFrancesco Taccari
Francesco Taccari
KRKelvin Rambiki
Kelvin Rambiki
TKTapiwa Kumwenda
Tapiwa Kumwenda
EBEnrico Brunetti
Enrico Brunetti
CWClaudia Wallrauch
Claudia Wallrauch
Background: The spleen is frequently scanned in workup of infections. Hypoechoic splenic micro-abscesses are known signs of disseminated tuberculosis in HIV co-infected patients. The spleen of HIV patients is thus often scanned using high-frequency transducers. Methods and findings: We describe a reticulo-nodular “sponge pattern” in the spleen of an HIV-positive patient with Hodgkin’s lymphoma. Disseminated throughout the spleen, very small (1.5–2.0 mm) hypoechoic lesions having a branching reticulo-nodular distribution were seen. The lesions partly, but not entirely, follow splenic vasculature. Review of stored images of other patients identified 15 more cases showing a similar pattern. All patients were HIV positive, almost all with CD4 counts below 200 cells/mm 3 . Seven (44%) were additionally diagnosed with HHV-8-associated diseases, but the pattern was seen with various underlying opportunistic infections. Discussion and conclusion: After comparison with spleen microscopic anatomy, we hypothesize that the white pulp of spleens in our patients is hyperplastic or otherwise changed in consistency to be better visible by high-frequency ultrasound. Concomitant human herpesvirus-8 infection may be another cause of this visible white pulp. While we can only speculate about the etiology of the splenic “sponge pattern,” it needs to be recognized as it may be misinterpreted as splenic micro-abscesses of disseminated infections, like tuberculosis in severely immune-compromised patients.

Verified
Journal Article
Open access
PDF file
TKTapiwa Kumwenda
Tapiwa Kumwenda
DHDaniel Zachary Hodson
Daniel Zachary Hodson
KRKelvin Rambiki
Kelvin Rambiki
EREthel Rambiki
Ethel Rambiki
YFYuri Fedoriw
Yuri Fedoriw
MPMatthew Painschab
Matthew Painschab
Kaposi sarcoma-associated herpes virus (KSHV), also known as human herpes virus 8 (HHV-8), is the primary etiologic cause of Kaposi sarcoma (KS) and KSHV Inflammatory Cytokine Syndrome (KICS). Patients with KICS demonstrate symptoms of systemic inflammation, high KSHV viral load, elevation of inflammatory markers, and increased mortality. Management requires rapid diagnosis, treatment of underlying HIV, direct treatment of KS, and addressing the hyperimmune response. While a case definition based on clinical presentation, imaging findings, laboratory values, KSHV viral load, and lymph-node biopsy has been proposed, some of the required investigations are frequently unavailable in resource-constrained settings. Due to these challenges, KICS likely remains underdiagnosed and undertreated in these settings. We report a case of a 19-year-old woman living with HIV, and intermittent adherence to her ART, who presented with hypotension and acute hypoxemic respiratory failure. She was found to have high KSHV and HIV viral loads, low CD4 count, anemia, thrombocytopenia, hypoalbuminemia, and elevated inflammatory markers. On bedside ultrasound, she was found to have bilateral pleural effusions, ascites, an enlarged spleen, and hyperechoic splenic lesions. The diagnosis of KICS was made based on this constellation of findings. Weighing the risk and benefits of steroid administration in KS patients, the patient was successfully treated by the continuation of ART and the initiation of paclitaxel chemotherapy and steroids. We propose an adapted case definition relevant to the resource-constrained context. Due to the dual burden of KSHV and HIV in sub-Saharan Africa, additional cases of KICS are likely, and this syndrome will contribute to the burden of early mortality in newly diagnosed HIV patients. Addressing the diagnostic and therapeutic challenges of KICS must be a part of the overall management of the HIV pandemic.

1 June 2023 in The Ultrasound Journal
Verified
Journal Article
Open access
PDF file
MHMichaela Aurelia Maria Huson
Michaela Aurelia Maria Huson
TKTapiwa Kumwenda
Tapiwa Kumwenda
JGJoe Gumulira
Joe Gumulira
EREthel Rambiki
Ethel Rambiki
CWClaudia Wallrauch
Claudia Wallrauch
THTom Heller
Tom Heller
Background: Focused Assessment with Sonography for HIV-associated TB (FASH) is a diagnostic tool for extra-pulmonary tuberculosis (TB) in symptomatic patients with advanced HIV. As Kaposi’s sarcoma (KS) is also prevalent in this patient population, changes due to KS may mimic TB findings and clinical interpretation of target FASH findings can be challenging. We aimed to describe sonographic findings in patients with KS. Methods: We performed a prospective observational study at Lighthouse clinic at Kamuzu Central Hospital, Lilongwe, Malawi, in consecutive patients with newly diagnosed KS, without known diagnosis of TB, referred for paclitaxel treatment. All patients underwent FASH and abdominal ultrasound to assess for effusions and changes in liver and spleen, as well as systematic sonographic assessment for lymphadenopathy. Results: We included 30 patients. We found inguinal lymph nodes using ultrasound in 20 patients; in 3 (10%) additionally abdominal lymph nodes were found. Pathological effusions were seen in eight patients (27%): pericardial effusion in one (3%), pleural effusion in six (20%) and ascites in four (13%) patients. We found focal spleen lesions in three (10%) patients. Most of these lesions were echogenic, but in one patient, we saw hypoechoic lesions with an echogenic center. In three (10%) patients an unusual “sponge-like pattern” of the splenic vasculature was found. Six (20%) patients had echogenic focal lesions in the liver resembling hemangiomas, individual lesions showing a hypoechoic center. In two patients echogenic portal fields were seen. Conclusions: The majority of patients with newly diagnosed KS demonstrate sonographic features of disease, predominantly lymphadenopathy. Effusions were observed in a significant minority, as well as focal lesions in liver or spleen, which commonly resemble hemangiomas, but hypoechoic lesions were also observed and can easily be mistaken for extra-pulmonary TB. A 'sponge-like pattern' of the spleen should not be confused with micro-abscesses. In conclusion, this case series illustrates the diverse nature of ultrasound features in patients with KS, which can be difficult to distinguish from other opportunistic diseases, including TB.