COVID-19: Effects in Comorbidities and Special Populations

In December 2019, cases of pneumonia emerged in Wuhan, China, which was indicated to be due to a novel coronavirus called SARS-CoV-2 or COVID-19. This virus shares a lot of similarities with the previous SARS-Cov and MERS-Cov, yet its spread has been recorded to be much faster, with more than 80 million cases and close to 1 million deaths in the USA by March 2022. Further, the CDC has released a list of health conditions that increase the risk of acquiring the virus and its severity by 12- folds. Those conditions include diabetes, cardiovascular diseases, chronic kidney disease, cancer, chronic obstructive pulmonary disease, sickle cell anemia, obesity, and immunocompromised states. The two common mechanisms increasing the susceptibility of patients with any of the aforementioned co-morbidities are 1) increased inflammation causing a “cytokine storm”; and 2) suppressed or delayed immune system response, which is expected to be highly responsive in infections. The “cytokine storm” is characterized by an increased release of cytokines that cause an impaired response of the macrophages and lymphocytes that are expected to be highly responsive under any state of infection. Further, these conditions are known to be states of chronic low-grade inflammation, which adds to the cytokine storm with the suppression of the immune response. This disruption equally influences the involvement of B-cells and T-cells in the resolution of infections. Finally, some conditions may suffer from disturbances at the levels of the respiratory system, such as difficulty breathing, accompanied by respiratory muscles inefficiency and inequality in ventilation perfusion, causing hypoxia and the increased need for mechanical ventilation and ICU admission. The objective of this chapter is to introduce the main chronic conditions mostly influenced by SARS-Cov-2, the severity of the virus, its prevalence among the recorded cases, and the consequence observed at the level of the immune system.

The novel coronavirus disease (COVID-19) has scourged the world since its outbreak in December 2019 in Wuhan, China. The disease tends to be asymptomatic or mild in nearly 80% of the patients. However, around 5% of the patients tend to have critical diseases complicated by acute respiratory distress syndrome (ARDS), shock, and multiple organ failure. The disease tends to be specifically severe in patients with advancing age and in those with underlying comorbidities. Diabetes mellitus has emerged as distinctive comorbidity that is associated with severe disease, acute respiratory distress syndrome, intensive care unit admission, and mortality in COVID- 19. The impaired innate immune system, underlying pro-inflammatory milieu, reduced expression of angiotensin-converting enzyme 2 (ACE2), and concomitant use of reninangiotensin- aldosterone system-active drugs are some of the proposed pathophysiological links between diabetes mellitus and COVID-19 severity. On the contrary, the presence of active COVID-19 infection in a patient with underlying diabetes mellitus leads to the worsening of glucose control. Although glucose control prior to hospital admission has not been consistently associated with clinical outcomes in diabetic patients with COVID-19, in-hospital good glycemic control is associated with a lower rate of complications and all-cause mortality.

The COVID-19 pandemic is an unprecedented event that has taken a toll on the care of people with chronic illness, especially diabetes and its complications. Foot complications in diabetes encompass the whole spectrum from “at-risk foot to”, neuropathic foot ulcer, diabetic foot infections, claudication, gangrene, and Charcot neuroarthropathy. Guidelines suggest annual foot examination in people with diabetes and more frequently in those with foot ulcers or vasculopathy. COVID-19 pandemic has necessitated a lack of face-to-face consultations or examination and reliance on telemedicine or video call facilities for interaction with the patients. We provide a useful guide for the physicians regarding the examination of the foot and early recognition of risk factors for foot ulcers, signs of foot infections, ischemic changes, and active Charcot foot. Diabetic foot infections (DFI) and infected foot ulcers carry poor prognoses as they may culminate in amputation and mortality. Hence, triage of patients to recognize the signs of life-threatening infections that mandate hospitalization is discussed. The serological tests, tissue culture, radiological imaging for the diagnosis of DFI, along with the choice of antibiotics for the treatment of DFI, are detailed. The diagnosis of Charcot foot is altogether difficult, but early identification of telltale signs through video consultation and appropriate offloading total contact cast will help these patients to prevent deformities and amputations. Overall, continued communication with video calls, telemedicine facility, and group chats, including Whatsapp, will encourage patients for self-examination of foot and aid in better management of diabetic foot during these testing times.

The world in 2020 has witnessed the spread of a novel coronavirus, the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which typically involves the respiratory tract causing symptoms like fever, cough and shortness of breath and, in severe cases leading to the development of acute respiratory distress syndrome (ARDS). As the disease has evolved across the globe, a large number of patients are being recognised with atypical symptoms, including abdominal pain, nausea, vomiting and diarrhea. Involvement of liver in form of elevated aminotransferases and association of increased severity of coronavirus disease of 2019 (COVID-19) with pre-existing chronic liver disease has also been noted. The detection of virus in saliva and faeces of patients has unveiled the possibility of faecal-oral transmission of the virus and the risk of transmission during endoscopic procedures. Liver transplant recipients or patients undergoing liver transplant also need specialised care during this pandemic because of the possible interplay of immunosuppression and SARS-CoV-2. Various drugs used in the treatment of COVID-19 can also cause gastrointestinal symptoms or drug induced liver injury (DILI). This review will focus on the symptomatology, mechanism and pathological findings of SARS-CoV-2 in the liver and gastrointestinal tract. We will also highlight safe endoscopy practices to curtail the spread of COVID-19 and implications of the disease in liver transplant recipients.

COVID-19 disease caused by Severe Acute Respiratory Syndrome CoronaVirus-2 (SARS-CoV-2) has rapidly established itself as a devastating pandemic of a larger magnitude. The most common symptoms of COVID-19 include fever, dry cough, myalgia, and fatigue. Severe symptoms and critical disease occur in 5 to 15% of patients, progressing to acute respiratory distress syndrome and multi-organ dysfunction syndrome. Risk factors for severe disease and death include old age, hypertension, diabetes, underlying cardiovascular and respiratory diseases, cancer, and obesity. The SARS-CoV-2 virus has broad tissue tropism, and a quarter of patients can have cardiac involvement. Cardiovascular (CV) manifestations include subclinical and overt myocarditis, acute coronary syndromes, arrhythmias, exacerbation of heart failure, thromboembolism, cardiogenic shock, and death. Patients with preexisting cardiovascular disease (CVD) or CV involvement during the course of illness may have poor clinical outcomes. Patients who have recovered from acute illness can have persistent long-term effects with clinical significance. The focus of this chapter is about the bidirectional interaction between COVID-19 disease and CVD, its various cardiovascular manifestations, their outcomes, and management.

COVID-19, the disease caused by SARS-CoV-2, is characterized by significant abnormalities of the hematopoietic as well as the hemostatic system. These abnormalities have important prognostic as well as therapeutic implications in the management of these patients. Lymphopenia has emerged as a cardinal manifestation of COVID-19, which correlates with the severity of the cytokine storm and confers an adverse prognosis. Although not associated with direct cytopathic effects of SARSCoV- 2, anemia and thrombocytopenia are commonly present, with increased incidence in critically ill patients. It has been suggested that an ineffective adoptive immune response may be responsible for the hyper-inflammatory state and cytokine response in patients with severe COVID-19. Dysregulation of the macrophage phenotype may be associated with secondary HLH like physiology with hyperferritinemia and multi-organ dysfunction. The coagulation abnormalities are characterized by normal or elevated fibrinogen levels and are distinct from DIC. This distinct coagulopathy is labelled as COVID coagulopathy. It is predominant due to local microangiopathy and endothelial dysfunction in involved organs, such as the pulmonary vasculature. The hypercoagulable state is associated with a higher risk of arterial and venous thrombosis and a trend towards an increase in vaso-occlusive events, such as myocardial infarction and stroke. The D-Dimer elevation is seen in approximately 50% of patients, and increasing value during hospitalization indicates a poor prognosis. Finally, a comprehensive understanding of these pathophysiological states may help us in devising treatment protocols with a combination of antiviral, anti-inflammatory, and anticoagulation strategies for best treatment outcomes.

The SARS-Coronavirus-19 disease has emerged as a global health challenge and has engulfed almost all countries since it was first reported in Wuhan, China. Patients with CKD have not been spared from the wrath of this pandemic and are bearing the brunt of it along with the rest of the population. Most of the patients with CKD have underlying comorbidities like diabetes and hypertension and are at an increased risk of adverse outcomes. Some of the manifestations of COVID-19 include proteinuria, hematuria, AKI, and acute CKD, requiring various forms of renal replacement therapy. Multiple mechanisms proposed for this damage include direct invasion, cytokine storm, hemodynamic derangements, and many others that are still undergoing extensive research. Since SARS COV 2 enters the cells through ACE 2 receptors, there are concerns regarding the use of ACE inhibitors and ARBs in patients already on these drugs. There are concerns regarding the use of immunosuppressants in various immune-mediated kidney diseases (postponing planned doses of methylprednisolone/cyclophosphamide/rituximab). Hemodialysis patients are exposed to potential sources of coronavirus as they have to repeatedly report to hospitals for their dialysis sessions. Measures regarding safeguarding dialysis staff from COVID -19 are contentious issues, especially in resource-limited settings. Almost all renal transplant patients are on lifelong immunosuppressive agents, making them more vulnerable to infections. Therefore, CKD patients have unique issues in the management of COVID and CKD, which we need to understand to develop protocols for the management of these problems.

The coronavirus disease 2019 (COVID-19) primarily affects the respiratory system, commonly manifesting as pneumonia. The clinical presentation of COVID-19 is challenging to distinguish from community-acquired pneumonia due to other etiologies and respiratory exacerbations of pre-existing chronic respiratory diseases. Fortunately, the majority of patients have an asymptomatic or mild illness. However, some patients may develop profound hypoxemia secondary to diffuse alveolar damage and occlusion of alveolar capillaries by microthrombi. When patients with compromised lung function due to pre-existing respiratory diseases develop this disease, they face a setback. The management of the pre-existing illness is often suboptimal due to COVID-19-related restrictions. Further, these patients are more likely to develop severe manifestations of COVID-19 resulting in more severe morbidity and mortality. Diagnosis is established by performing a reverse transcription-polymerase chain reaction (RT-PCR) on samples from the respiratory tract. Treatment of the mild disease is primarily supportive, while supplemental oxygen and mechanical ventilation may be indicated for more severe cases. Several treatment options, including antiviral agents, corticosteroids, immunomodulators, and convalescent plasma therapy, are being investigated. Currently, there is no evidence to indicate that the diagnosis and treatment of COVID-19 are different in those with preexisting respiratory conditions. In the absence of an effective antiviral agent or vaccine, disease prevention is assumed to be of paramount importance. Social distancing and proper use of personal protective equipment are critical in the prevention of transmission.

The SARS-CoV-2 pandemic has emerged as an unprecedented challenge to the current medical practice, including obstetrics. Being an acute situation, there is limited experience of the impact of COVID-19 in pregnancy. Various management protocols are being evaluated and modified frequently to address key concerns of maternal and neonatal health. Pregnancy is a unique bundle of two lives, and the physiological adaptation to the dual life adds to the uniqueness. The effect of COVID- 19 and its treatment on pregnancy (mother and fetus) and vice-versa, is a common quest for all pathologies. The other concerns are vertical and horizontal transmission in antepartum, intrapartum, and postpartum periods, respectively. The immunosuppression as a part of physiological changes during pregnancy apparently raises apprehension of higher risk of viral infection or probability of severity of infection during pregnancy. The same has also been observed with previous virus infections in history like severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), etc., although available literature suggests that the risk of developing COVID-19 for pregnant women is not similar to the non-pregnant adult population. The small risk of developing a serious condition during pregnancy is inevitable, and the contagiousness of the virus is a major concern for the neonate and attending family. Some overlapping features of complicated pregnancy with severe COVID-19 require attention. Social distancing, anxiety, and psychological stress need to be kept in mind. There is an impact of financial stress on family; domestic violence can also not be undermined during this crisis period. Access to health facilities may also be affected in developing countries due to the lockdowns, quarantine of pregnant women, caretakers, or health care workers (HCW), etc. The aerosol production during the intrapartum phase is challenging for both vaginal and abdominal routes of delivery, but the management of sudden catastrophic, life-threatening conditions associated with pregnancy can be a real threat for the team of health care workers. It is still early to comment on the long-term effects of the viral infection on the foetus, especially the exposure during the rapid embryogenesis period.

An adult patient with COVID-19 usually presents with symptoms of flu like dry cough, myalgia, headache, fever with chills, breathing difficulty and sore throat. Unlike common flu, acute anosmia without nasal obstruction, hyposmia and dysgeusia are considered as early signs and warrant self-isolation and testing. Children usually have milder symptoms with a good prognoses. Nasopharynx and oropharynx being the reservoirs of the viral load, Otolaryngologist becomes the most vulnerable for infection transmission while screening, sampling or operating on any such patient. 

Ocular involvement in COVID-19 is extremely low, and manifests mainly as conjunctivitis, in the form of conjunctival hyperaemia, chemosis, increased secretions and/or epiphora. Although it is presumed to be self-limiting, tears are potential source of SARS-CoV-2 transmission. The nature and proximity of ophthalmic examination makes the eye care personnel highly prone to COVID-19 infection. There are reports of ophthalmologists getting infected with COVID-19, and succumbing to this disease. Besides the recommended practice guidelines, surgical interventions in ENT and ophthalmology practice should be limited to urgent and semi-urgent indications.

COVID 19 has already affected more than 191 million people worldwide and has claimed more than 4 million lives to date (22nd July 2021). Yet, we still do not completely understand this disease. Data on children are even more sparse, making it difficult to lay down a comprehensive guideline for the same. 

However, thanks to a handful of studies, we now understand that children are less affected, are less infectious, have lesser mortality and risk of complications. Children with underlying chronic diseases and infants under 1 year are especially at risk and are advised selective shielding. Diagnosis is done by RT-PCR or serology, just like in adults. Most affected children are asymptomatic, and even the symptomatic children have a good outcome and usually need supportive management and monitoring only. Up to 7% of children were found to require PICU support, and mortality was less than 2%. Most deaths were attributed to underlying conditions and immunological complications, especially MIS-C. Treatment is predominantly supportive, with little consensus on specific treatments, including corticosteroids, remdesivir, and IVIg. Management is best individualized by a multidisciplinary team involving pediatricians, hematologists, immunologists, and intensivists. Prevention of COVID 19 can be achieved by proper hygiene, face masks, and social distancing. The upcoming vaccines are expected to bring down the cases and hopefully bring this pandemic to a halt.

The second pandemic of the 21st century, the Coronavirus Disease – 2019, has kept the entire world on its toes. The virus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), seems to have an entire deck of tricks up its sleeve. The brash and acerbic disease course has left the entire world gasping. A sour understanding of the virus evolves, our knowledge base at this point is rather nascent. While the rate of infection is highest among the younger age groups, the Case Fatality Rate seems to be five to seven-fold higher in patients aged 65 years and above. With unforeseen restraints and stern preventive policies in place worldwide, the core principles of Geriatrics seem to have taken a backseat. Social distancing might’ve turned into social suppression, and the phenomena of immunosenescence and frailty leave our elderly population with an oligosymptomatic illness, which is, on many occasions, neglected on a personal, familial or even healthcare level, thus, erring on the gravity of the illness. Patients and medical personnel in hospice facilities and long-term care facilities (LTCFs) face unique and unprecedented challenges. With atypical presentations, multimorbidities, and multiple psychosocial facets, the Coronavirus Disease-2019 presents a rather interesting challenge in the care and management of older adults.